initial commit of C# transport changes

49 files changed, 2479 insertions, 2406 deletions

diff --git a/cpp/src/Ice/IPEndpointI.cpp b/cpp/src/Ice/IPEndpointI.cpp
index 7bf4a057c63..a94f05ce429 100644
--- a/cpp/src/Ice/IPEndpointI.cpp
+++ b/cpp/src/Ice/IPEndpointI.cpp
@@ -185,6 +185,7 @@ IceInternal::IPEndpointI::hash() const
         _hashValue = 5381;
         hashAdd(_hashValue, type());
         hashInit(_hashValue);
+        _hashInitialized = true;
     }
     return _hashValue;
 }
diff --git a/cs/src/Ice/Acceptor.cs b/cs/src/Ice/Acceptor.cs
index 82552b9d81b..897a1ca7f19 100644
--- a/cs/src/Ice/Acceptor.cs
+++ b/cs/src/Ice/Acceptor.cs
@@ -20,6 +20,7 @@ namespace IceInternal
         bool startAccept(AsyncCallback callback, object state);
         void finishAccept();
         Transceiver accept();
+        string protocol();
         string ToString();
     }
 
diff --git a/cs/src/Ice/ConnectionI.cs b/cs/src/Ice/ConnectionI.cs
index 363656c0c18..065b4f6da32 100644
--- a/cs/src/Ice/ConnectionI.cs
+++ b/cs/src/Ice/ConnectionI.cs
@@ -227,7 +227,7 @@ namespace Ice
         public bool isFinished()
         {
             //
-            // We can use TryEnter here, because as long as there are still
+            // We can use TryLock here, because as long as there are still
             // threads operating in this connection object, connection
             // destruction is considered as not yet finished.
             //
@@ -244,12 +244,12 @@ namespace Ice
                 }
 
                 Debug.Assert(_state == StateFinished);
+                return true;
             }
             finally
             {
                 _m.Unlock();
             }
-            return true;
         }
 
         public void throwException()
@@ -301,7 +301,7 @@ namespace Ice
                     _m.Wait();
                 }
 
-                Debug.Assert(_state == StateFinished && _dispatchCount == 0);
+                Debug.Assert(_state == StateFinished);
 
                 //
                 // Clear the OA. See bug 1673 for the details of why this is necessary.
@@ -551,7 +551,7 @@ namespace Ice
                 bool sent;
                 try
                 {
-                    OutgoingMessage msg = new OutgoingMessage(og, og.ostr__, compress, requestId);
+                    OutgoingMessage msg = new OutgoingMessage(og, os, compress, requestId);
                     sent = sendMessage(msg);
                     sentCallback = msg.sentCallback;
                 }
@@ -873,6 +873,9 @@ namespace Ice
 
                 _batchStream.swap(@out.ostr());
 
+                //
+                // Send the batch stream.
+                //
                 bool sent = false;
                 try
                 {
@@ -971,6 +974,10 @@ namespace Ice
             _m.Lock();
             try
             {
+                if(_state > StateClosing)
+                {
+                    return;
+                }
                 _callback = callback;
             }
             finally
@@ -1234,7 +1241,6 @@ namespace Ice
                 {
                     return;
                 }
-                Debug.Assert(_state < StateClosing);
 
                 _adapter = adapter;
 
@@ -1305,7 +1311,7 @@ namespace Ice
                 {
                     if(_observer != null)
                     {
-                        observerStartWrite(_writeStream.pos());
+                        observerStartWrite(_writeStream.getBuffer());
                     }
 
                     bool completed;
@@ -1320,8 +1326,9 @@ namespace Ice
                 {
                     if(_observer != null && !_readHeader)
                     {
-                        observerStartRead(_readStream.pos());
+                        observerStartRead(_readStream.getBuffer());
                     }
+
                     completedSynchronously = _transceiver.startRead(_readStream.getBuffer(), cb, this);
                 }
             }
@@ -1342,7 +1349,7 @@ namespace Ice
                     _transceiver.finishWrite(_writeStream.getBuffer());
                     if(_observer != null)
                     {
-                        observerFinishWrite(_writeStream.pos());
+                        observerFinishWrite(_writeStream.getBuffer());
                     }
                 }
                 else if((operation & IceInternal.SocketOperation.Read) != 0)
@@ -1350,7 +1357,7 @@ namespace Ice
                     _transceiver.finishRead(_readStream.getBuffer());
                     if(_observer != null && !_readHeader)
                     {
-                        observerFinishRead(_readStream.pos());
+                        observerFinishRead(_readStream.getBuffer());
                     }
                 }
             }
@@ -1381,36 +1388,48 @@ namespace Ice
                     return;
                 }
 
+                int readyOp = current.operation;
                 try
                 {
                     unscheduleTimeout(current.operation);
-                    if((current.operation & IceInternal.SocketOperation.Write) != 0 && !_writeStream.isEmpty())
+
+                    int writeOp = IceInternal.SocketOperation.None;
+                    int readOp = IceInternal.SocketOperation.None;
+                    if((readyOp & IceInternal.SocketOperation.Write) != 0)
                     {
                         if(_observer != null)
                         {
-                            observerStartWrite(_writeStream.pos());
+                            observerStartWrite(_writeStream.getBuffer());
                         }
-                        if(_writeStream.getBuffer().b.hasRemaining() && !_transceiver.write(_writeStream.getBuffer()))
+                        writeOp = _transceiver.write(_writeStream.getBuffer());
+                        if(_observer != null && (writeOp & IceInternal.SocketOperation.Write) == 0)
                         {
-                            Debug.Assert(!_writeStream.isEmpty());
-                            scheduleTimeout(IceInternal.SocketOperation.Write, _endpoint.timeout());
-                            return;
+                            observerFinishWrite(_writeStream.getBuffer());
                         }
-                        if(_observer != null)
-                        {
-                            observerFinishWrite(_writeStream.pos());
-                        }
-                        Debug.Assert(!_writeStream.getBuffer().b.hasRemaining());
                     }
-                    if((current.operation & IceInternal.SocketOperation.Read) != 0 && !_readStream.isEmpty())
+
+                    while((readyOp & IceInternal.SocketOperation.Read) != 0)
                     {
+                        IceInternal.Buffer buf = _readStream.getBuffer();
+
+                        if(_observer != null && !_readHeader)
+                        {
+                            observerStartRead(buf);
+                        }
+
+                        readOp = _transceiver.read(buf, ref _hasMoreData);
+                        if((readOp & IceInternal.SocketOperation.Read) != 0)
+                        {
+                            break;
+                        }
+                        if(_observer != null && !_readHeader)
+                        {
+                            Debug.Assert(!buf.b.hasRemaining());
+                            observerFinishRead(buf);
+                        }
+
                         if(_readHeader) // Read header if necessary.
                         {
-                            if(_readStream.getBuffer().b.hasRemaining() && !_transceiver.read(_readStream.getBuffer()))
-                            {
-                                return;
-                            }
-                            Debug.Assert(!_readStream.getBuffer().b.hasRemaining());
                             _readHeader = false;
 
                             if(_observer != null)
@@ -1466,35 +1485,34 @@ namespace Ice
                             _readStream.pos(pos);
                         }
 
-                        if(_readStream.getBuffer().b.hasRemaining())
+                        if(buf.b.hasRemaining())
                         {
                             if(_endpoint.datagram())
                             {
                                 throw new Ice.DatagramLimitException(); // The message was truncated.
                             }
-                            else
-                            {
-                                if(_observer != null)
-                                {
-                                    observerStartRead(_readStream.pos());
-                                }
-                                if(!_transceiver.read(_readStream.getBuffer()))
-                                {
-                                    Debug.Assert(!_readStream.isEmpty());
-                                    scheduleTimeout(IceInternal.SocketOperation.Read, _endpoint.timeout());
-                                    return;
-                                }
-                                if(_observer != null)
-                                {
-                                    observerFinishRead(_readStream.pos());
-                                }
-                                Debug.Assert(!_readStream.getBuffer().b.hasRemaining());
-                            }
+                            continue;
                         }
+                        break;
                     }
 
+                    int newOp = readOp | writeOp;
+                    readyOp &= ~newOp;
+                    Debug.Assert(readyOp != 0 || newOp != 0);
+
                     if(_state <= StateNotValidated)
                     {
+                        if(newOp != 0)
+                        {
+                            //
+                            // Wait for all the transceiver conditions to be
+                            // satisfied before continuing.
+                            //
+                            scheduleTimeout(newOp);
+                            _threadPool.update(this, current.operation, newOp);
+                            return;
+                        }
+
                         if(_state == StateNotInitialized && !initialize(current.operation))
                         {
                             return;
@@ -1515,44 +1533,52 @@ namespace Ice
                         {
                             startCB = _startCallback;
                             _startCallback = null;
-                            ++_dispatchCount;
+                            if(startCB != null)
+                            {
+                                ++_dispatchCount;
+                            }
                         }
                     }
                     else
                     {
-                        Debug.Assert(_state <= StateClosing);
+                        Debug.Assert(_state <= StateClosingPending);
 
                         //
                         // We parse messages first, if we receive a close
                         // connection message we won't send more messages.
                         // 
-                        if((current.operation & IceInternal.SocketOperation.Read) != 0)
+                        if((readyOp & IceInternal.SocketOperation.Read) != 0)
                         {
-                            parseMessage(ref info);
+                            newOp |= parseMessage(ref info);
                         }
 
-                        if((current.operation & IceInternal.SocketOperation.Write) != 0)
+                        if((readyOp & IceInternal.SocketOperation.Write) != 0)
                         {
-                            sentCBs = sendNextMessage();
-                            if(sentCBs != null)
+                            sentCBs = new Queue<OutgoingMessage>();
+                            newOp |= sendNextMessage(sentCBs);
+                            if(sentCBs.Count > 0)
                             {
                                 ++_dispatchCount;
                             }
+                            else
+                            {
+                                sentCBs = null;
+                            }
                         }
-                    }
 
-                    if(_acmLastActivity > 0)
-                    {
-                        _acmLastActivity = IceInternal.Time.currentMonotonicTimeMillis();
-                    }
+                        if(_state < StateClosed)
+                        {
+                            scheduleTimeout(newOp);
+                            _threadPool.update(this, current.operation, newOp);
+                        }
 
-                    if(startCB == null && sentCBs == null && info.invokeNum == 0 && info.outAsync == null && 
-                       info.heartbeatCallback == null)
-                    {
-                        return; // Nothing to dispatch.
-                    }
+                        if(readyOp == 0)
+                        {
+                            return;
+                        }
 
-                    msg.completed(ref current);
+                        msg.completed(ref current);
+                    }
                 }
                 catch(DatagramLimitException) // Expected.
                 {
@@ -1594,6 +1620,11 @@ namespace Ice
                     msg.finishIOScope(ref current);
                 }
 
+                if(_acmLastActivity > 0)
+                {
+                    _acmLastActivity = IceInternal.Time.currentMonotonicTimeMillis();
+                }
+
                 //
                 // Unlike C++/Java, this method is called from an IO thread of the .NET thread
                 // pool or from the communicator async IO thread. While it's fine to handle the
@@ -1692,13 +1723,13 @@ namespace Ice
                 ++count;
             }
 
+            //
+            // Method invocation (or multiple invocations for batch messages)
+            // must be done outside the thread synchronization, so that nested
+            // calls are possible.
+            //
             if(info.invokeNum > 0)
             {
-                //
-                // Method invocation (or multiple invocations for batch messages)
-                // must be done outside the thread synchronization, so that nested
-                // calls are possible.
-                //
                 invokeAll(info.stream, info.invokeNum, info.requestId, info.compress, info.servantManager,
                           info.adapter);
 
@@ -1725,7 +1756,7 @@ namespace Ice
                         // or AMI callback was dispatched when the connection
                         // was already in the closing state.
                         //
-                        if(_state == StateClosing && !_shutdownInitiated)
+                        if(_state == StateClosing)
                         {
                             try
                             {
@@ -1768,7 +1799,7 @@ namespace Ice
             // to call code that will potentially block (this avoids promoting a new leader and
             // unecessary thread creation, especially if this is called on shutdown).
             //
-            if(_startCallback == null && _sendStreams.Count == 0 && _asyncRequests.Count == 0)
+            if(_startCallback == null && _sendStreams.Count == 0 && _asyncRequests.Count == 0 && _callback == null)
             {
                 finish();
                 return;
@@ -1783,7 +1814,11 @@ namespace Ice
             _threadPool.execute(
                 delegate()
                 {
-                    if(_dispatcher != null)
+                    if(_dispatcher == null)
+                    {
+                        finish();
+                    }
+                    else
                     {
                         try
                         {
@@ -1798,10 +1833,6 @@ namespace Ice
                             }
                         }
                     }
-                    else
-                    {
-                        finish();
-                    }
                 });
         }
 
@@ -1823,21 +1854,19 @@ namespace Ice
                     //
                     OutgoingMessage message = _sendStreams.First.Value;
                     _writeStream.swap(message.stream);
-                    
+
                     //
                     // The current message might be sent but not yet removed from _sendStreams. If
                     // the response has been received in the meantime, we remove the message from
                     // _sendStreams to not call finished on a message which is already done.
                     //
-                    if(message.requestId > 0 &&
-                       (message.@out != null && !_requests.ContainsKey(message.requestId) ||
-                        message.outAsync != null && !_asyncRequests.ContainsKey(message.requestId)))
+                    if(message.replyOutAsync != null)
                     {
-                        if(message.sent(this))
+                        if(message.sent() && message.sentCallback != null)
                         {
-                            Debug.Assert(message.outAsync != null);
                             message.outAsync.invokeSent__(message.sentCallback);
                         }
+                        message.replyOutAsync.finished__();
                         _sendStreams.RemoveFirst();
                     }
                 }
@@ -1922,7 +1951,7 @@ namespace Ice
                 {
                     setState(StateClosed, new TimeoutException());
                 }
-                else if(_state == StateClosing)
+                else if(_state < StateClosed)
                 {
                     setState(StateClosed, new CloseTimeoutException());
                 }
@@ -1992,9 +2021,8 @@ namespace Ice
 
                 if(invokeNum > 0)
                 {
-                    Debug.Assert(_dispatchCount > 0);
+                    Debug.Assert(_dispatchCount >= invokeNum);
                     _dispatchCount -= invokeNum;
-                    Debug.Assert(_dispatchCount >= 0);
                     if(_dispatchCount == 0)
                     {
                         if(_state == StateFinished)
@@ -2023,23 +2051,21 @@ namespace Ice
             _communicator = communicator;
             _instance = instance;
             _monitor = monitor;
-            InitializationData initData = instance.initializationData();
             _transceiver = transceiver;
             _desc = transceiver.ToString();
-            _type = transceiver.type();
+            _type = transceiver.protocol();
             _connector = connector;
             _endpoint = endpoint;
             _adapter = adapter;
+            InitializationData initData = instance.initializationData();
             _dispatcher = initData.dispatcher; // Cached for better performance.
             _logger = initData.logger; // Cached for better performance.
             _traceLevels = instance.traceLevels(); // Cached for better performance.
             _timer = instance.timer();
             _writeTimeout = new TimeoutCallback(this);
             _writeTimeoutScheduled = false;
-            _writeStreamPos = -1;
             _readTimeout = new TimeoutCallback(this);
             _readTimeoutScheduled = false;
-            _readStreamPos = -1;
             _warn = initData.properties.getPropertyAsInt("Ice.Warn.Connections") > 0;
             _warnUdp = initData.properties.getPropertyAsInt("Ice.Warn.Datagrams") > 0;
             _cacheBuffers = initData.properties.getPropertyAsIntWithDefault("Ice.CacheMessageBuffers", 1) == 1;
@@ -2060,7 +2086,9 @@ namespace Ice
             _batchMarker = 0;
             _readStream = new IceInternal.BasicStream(instance, Util.currentProtocolEncoding);
             _readHeader = false;
+            _readStreamPos = -1;
             _writeStream = new IceInternal.BasicStream(instance, Util.currentProtocolEncoding);
+            _writeStreamPos = -1;
             _dispatchCount = 0;
             _state = StateNotInitialized;
 
@@ -2107,8 +2135,9 @@ namespace Ice
         private const int StateActive = 2;
         private const int StateHolding = 3;
         private const int StateClosing = 4;
-        private const int StateClosed = 5;
-        private const int StateFinished = 6;
+        private const int StateClosingPending = 5;
+        private const int StateClosed = 6;
+        private const int StateFinished = 7;
 
         private void setState(int state, LocalException ex)
         {
@@ -2125,6 +2154,11 @@ namespace Ice
 
             if(_exception == null)
             {
+                //
+                // If we are in closed state, an exception must be set.
+                //
+                Debug.Assert(_state != StateClosed);
+
                 _exception = ex;
 
                 //
@@ -2140,7 +2174,7 @@ namespace Ice
                          _exception is ConnectionTimeoutException ||
                          _exception is CommunicatorDestroyedException ||
                          _exception is ObjectAdapterDeactivatedException ||
-                         (_exception is ConnectionLostException && _state == StateClosing)))
+                         (_exception is ConnectionLostException && _state >= StateClosing)))
                     {
                         warning("connection exception", _exception);
                     }
@@ -2231,21 +2265,15 @@ namespace Ice
                 }
 
                 case StateClosing:
+                case StateClosingPending:
                 {
                     //
-                    // Can't change back from closed.
+                    // Can't change back from closing pending.
                     //
-                    if(_state >= StateClosed)
+                    if(_state >= StateClosingPending)
                     {
                         return;
                     }
-                    if(_state == StateHolding)
-                    {
-                        //
-                        // We need to continue to read in closing state.
-                        //
-                        _threadPool.register(this, IceInternal.SocketOperation.Read);
-                    }
                     break;
                 }
 
@@ -2255,6 +2283,7 @@ namespace Ice
                     {
                         return;
                     }
+
                     _threadPool.finish(this);
                     _transceiver.close();
                     break;
@@ -2322,7 +2351,7 @@ namespace Ice
                          _exception is ConnectionTimeoutException ||
                          _exception is CommunicatorDestroyedException ||
                          _exception is ObjectAdapterDeactivatedException ||
-                         (_exception is ConnectionLostException && _state == StateClosing)))
+                         (_exception is ConnectionLostException && _state >= StateClosing)))
                     {
                         _observer.failed(_exception.ice_name());
                     }
@@ -2349,15 +2378,17 @@ namespace Ice
         {
             Debug.Assert(_state == StateClosing);
             Debug.Assert(_dispatchCount == 0);
-            Debug.Assert(!_shutdownInitiated);
 
+            if(_shutdownInitiated)
+            {
+                return;
+            }
             _shutdownInitiated = true;
 
             if(!_endpoint.datagram())
             {
                 //
-                // Before we shut down, we send a close connection
-                // message.
+                // Before we shut down, we send a close connection message.
                 //
                 IceInternal.BasicStream os = new IceInternal.BasicStream(_instance, Util.currentProtocolEncoding);
                 os.writeBlob(IceInternal.Protocol.magic);
@@ -2369,28 +2400,22 @@ namespace Ice
 
                 if(sendMessage(new OutgoingMessage(os, false, false)))
                 {
+                    setState(StateClosingPending);
+
                     //
-                    // Schedule the close timeout to wait for the peer to close the connection. If
-                    // the message was queued for sending, sendNextMessage will schedule the timeout
-                    // once all messages were sent.
+                    // Notify the the transceiver of the graceful connection closure.
                     //
-                    scheduleTimeout(IceInternal.SocketOperation.Write, closeTimeout());
+                    int op = _transceiver.closing(true, _exception);
+                    if(op != 0)
+                    {
+                        scheduleTimeout(op);
+                        _threadPool.register(this, op);
+                    }
                 }
-
-                //
-                // The CloseConnection message should be sufficient. Closing the write
-                // end of the socket is probably an artifact of how things were done
-                // in IIOP. In fact, shutting down the write end of the socket causes
-                // problems on Windows by preventing the peer from using the socket.
-                // For example, the peer is no longer able to continue writing a large
-                // message after the socket is shutdown.
-                //
-                //_transceiver.shutdownWrite();
             }
         }
 
-        private void
-        heartbeat()
+        private void heartbeat()
         {
             Debug.Assert(_state == StateActive);
             
@@ -2418,10 +2443,10 @@ namespace Ice
 
         private bool initialize(int operation)
         {
-            int s = _transceiver.initialize();
+            int s = _transceiver.initialize(_readStream.getBuffer(), _writeStream.getBuffer(), ref _hasMoreData);
             if(s != IceInternal.SocketOperation.None)
             {
-                scheduleTimeout(s, connectTimeout());
+                scheduleTimeout(s);
                 _threadPool.update(this, operation, s);
                 return false;
             }
@@ -2431,6 +2456,7 @@ namespace Ice
             //
             _desc = _transceiver.ToString();
             setState(StateNotValidated);
+
             return true;
         }
 
@@ -2454,17 +2480,23 @@ namespace Ice
 
                     if(_observer != null)
                     {
-                        observerStartWrite(_writeStream.pos());
+                        observerStartWrite(_writeStream.getBuffer());
                     }
-                    if(_writeStream.pos() != _writeStream.size() && !_transceiver.write(_writeStream.getBuffer()))
+
+                    if(_writeStream.pos() != _writeStream.size())
                     {
-                        scheduleTimeout(IceInternal.SocketOperation.Write, connectTimeout());
-                        _threadPool.update(this, operation, IceInternal.SocketOperation.Write);
-                        return false;
+                        int op = _transceiver.write(_writeStream.getBuffer());
+                        if(op != 0)
+                        {
+                            scheduleTimeout(op);
+                            _threadPool.update(this, operation, op);
+                            return false;
+                        }
                     }
+
                     if(_observer != null)
                     {
-                        observerFinishWrite(_writeStream.pos());
+                        observerFinishWrite(_writeStream.getBuffer());
                     }
                 }
                 else // The client side has the passive role for connection validation.
@@ -2477,17 +2509,23 @@ namespace Ice
 
                     if(_observer != null)
                     {
-                        observerStartRead(_readStream.pos());
+                        observerStartRead(_readStream.getBuffer());
                     }
-                    if(_readStream.pos() != _readStream.size() && !_transceiver.read(_readStream.getBuffer()))
+
+                    if(_readStream.pos() != _readStream.size())
                     {
-                        scheduleTimeout(IceInternal.SocketOperation.Read, connectTimeout());
-                        _threadPool.update(this, operation, IceInternal.SocketOperation.Read);
-                        return false;
+                        int op = _transceiver.read(_readStream.getBuffer(), ref _hasMoreData);
+                        if(op != 0)
+                        {
+                            scheduleTimeout(op);
+                            _threadPool.update(this, operation, op);
+                            return false;
+                        }
                     }
+
                     if(_observer != null)
                     {
-                        observerFinishRead(_readStream.pos());
+                        observerFinishRead(_readStream.getBuffer());
                     }
 
                     Debug.Assert(_readStream.pos() == IceInternal.Protocol.headerSize);
@@ -2504,6 +2542,7 @@ namespace Ice
                     ProtocolVersion pv  = new ProtocolVersion();
                     pv.read__(_readStream);
                     IceInternal.Protocol.checkSupportedProtocol(pv);
+
                     EncodingVersion ev = new EncodingVersion();
                     ev.read__(_readStream);
                     IceInternal.Protocol.checkSupportedProtocolEncoding(ev);
@@ -2535,12 +2574,21 @@ namespace Ice
             return true;
         }
 
-        private Queue<OutgoingMessage> sendNextMessage()
+        private int sendNextMessage(Queue<OutgoingMessage> callbacks)
         {
-            Debug.Assert(_sendStreams.Count > 0);
-            Debug.Assert(!_writeStream.isEmpty() && _writeStream.pos() == _writeStream.size());
+            if(_sendStreams.Count == 0)
+            {
+                return IceInternal.SocketOperation.None;
+            }
+            else if(_state == StateClosingPending && _writeStream.pos() == 0)
+            {
+                // Message wasn't sent, empty the _writeStream, we're not going to send more data.
+                OutgoingMessage message = _sendStreams.First.Value;
+                _writeStream.swap(message.stream);
+                return IceInternal.SocketOperation.None;
+            }
 
-            Queue<OutgoingMessage> callbacks = null;
+            Debug.Assert(!_writeStream.isEmpty() && _writeStream.pos() == _writeStream.size());
             try
             {
                 while(true)
@@ -2550,14 +2598,8 @@ namespace Ice
                     //
                     OutgoingMessage message = _sendStreams.First.Value;
                     _writeStream.swap(message.stream);
-                    Debug.Assert(_writeStream.isEmpty());
-                    if(message.sent(this) || message.replyOutAsync != null)
+                    if(message.sent())
                     {
-                        Debug.Assert(message.outAsync != null);
-                        if(callbacks == null)
-                        {
-                            callbacks = new Queue<OutgoingMessage>();
-                        }
                         callbacks.Enqueue(message);
                     }
                     _sendStreams.RemoveFirst();
@@ -2571,17 +2613,17 @@ namespace Ice
                     }
 
                     //
-                    // If we are in the closed state, don't continue sending.
+                    // If we are in the closed state or if the close is
+                    // pending, don't continue sending.
                     //
-                    // The connection can be in the closed state if parseMessage
-                    // (called before sendNextMessage by message()) closes the
-                    // connection.
-                    // 
-                    if(_state >= StateClosed)
+                    // This can occur if parseMessage (called before
+                    // sendNextMessage by message()) closes the connection.
+                    //
+                    if(_state >= StateClosingPending)
                     {
-                        return callbacks;
+                        return IceInternal.SocketOperation.None;
                     }
-                
+
                     //
                     // Otherwise, prepare the next message stream for writing.
                     //
@@ -2608,45 +2650,49 @@ namespace Ice
                     //
                     if(_observer != null)
                     {
-                        observerStartWrite(_writeStream.pos());
+                        observerStartWrite(_writeStream.getBuffer());
                     }
-                    if(_writeStream.pos() != _writeStream.size() && !_transceiver.write(_writeStream.getBuffer()))
+                    if(_writeStream.pos() != _writeStream.size())
                     {
-                        Debug.Assert(!_writeStream.isEmpty());
-                        scheduleTimeout(IceInternal.SocketOperation.Write, _endpoint.timeout());
-                        return callbacks;
+                        int op = _transceiver.write(_writeStream.getBuffer());
+                        if(op != 0)
+                        {
+                            return op;
+                        }
                     }
                     if(_observer != null)
                     {
-                        observerFinishWrite(_writeStream.pos());
+                        observerFinishWrite(_writeStream.getBuffer());
                     }
                 }
             }
             catch(Ice.LocalException ex)
             {
                 setState(StateClosed, ex);
-                return callbacks;
+                return IceInternal.SocketOperation.None;
             }
 
-            Debug.Assert(_writeStream.isEmpty());
-            _threadPool.unregister(this, IceInternal.SocketOperation.Write);
-
             //
             // If all the messages were sent and we are in the closing state, we schedule
             // the close timeout to wait for the peer to close the connection.
             //
             if(_state == StateClosing)
             {
-                scheduleTimeout(IceInternal.SocketOperation.Write, closeTimeout());
+                setState(StateClosingPending);
+                int op = _transceiver.closing(true, _exception);
+                if(op != 0)
+                {
+                    return op;
+                }
             }
 
-            return callbacks;
+            return IceInternal.SocketOperation.None;
         }
 
-
         private bool sendMessage(OutgoingMessage message)
         {
             Debug.Assert(_state < StateClosed);
+
             if(_sendStreams.Count > 0)
             {
                 message.adopt();
@@ -2677,29 +2723,36 @@ namespace Ice
                 IceInternal.TraceUtil.traceSend(stream, _logger, _traceLevels);
             }
 
+            //
+            // Send the message without blocking.
+            //
             if(_observer != null)
             {
-                observerStartWrite(message.stream.pos());
+                observerStartWrite(message.stream.getBuffer());
             }
-            if(_transceiver.write(message.stream.getBuffer()))
+            int op = _transceiver.write(message.stream.getBuffer());
+            if(op == 0)
             {
                 if(_observer != null)
                 {
-                    observerFinishWrite(message.stream.pos());
+                    observerFinishWrite(message.stream.getBuffer());
                 }
-                message.sent(this);
+
+                message.sent();
+
                 if(_acmLastActivity > 0)
                 {
                     _acmLastActivity = IceInternal.Time.currentMonotonicTimeMillis();
                 }
                 return true;
             }
+
             message.adopt();
 
             _writeStream.swap(message.stream);
             _sendStreams.AddLast(message);
-            scheduleTimeout(IceInternal.SocketOperation.Write, _endpoint.timeout());
-            _threadPool.register(this, IceInternal.SocketOperation.Write);
+            scheduleTimeout(op);
+            _threadPool.register(this, op);
             return false;
         }
 
@@ -2764,7 +2817,7 @@ namespace Ice
             public ConnectionCallback heartbeatCallback;
         }
 
-        private void parseMessage(ref MessageInfo info)
+        private int parseMessage(ref MessageInfo info)
         {
             Debug.Assert(_state > StateNotValidated && _state < StateClosed);
 
@@ -2774,6 +2827,8 @@ namespace Ice
             _readStream.pos(0);
             _readHeader = true;
 
+            Debug.Assert(info.stream.pos() == info.stream.size());
+
             //
             // Connection is validated on first message. This is only used by
             // setState() to check wether or not we can print a connection
@@ -2787,7 +2842,6 @@ namespace Ice
                 //
                 // The magic and version fields have already been checked.
                 //
-                Debug.Assert(info.stream.pos() == info.stream.size());
                 info.stream.pos(8);
                 byte messageType = info.stream.readByte();
                 info.compress = info.stream.readByte();
@@ -2820,14 +2874,24 @@ namespace Ice
                         }
                         else
                         {
-                            setState(StateClosed, new CloseConnectionException());
+                            setState(StateClosingPending, new CloseConnectionException());
+
+                            //
+                            // Notify the the transceiver of the graceful connection closure.
+                            //
+                            int op = _transceiver.closing(false, _exception);
+                            if(op != 0)
+                            {
+                                return op;
+                            }
+                            setState(StateClosed);
                         }
                         break;
                     }
 
                     case IceInternal.Protocol.requestMsg:
                     {
-                        if(_state == StateClosing)
+                        if(_state >= StateClosing)
                         {
                             IceInternal.TraceUtil.trace("received request during closing\n" +
                                                         "(ignored by server, client will retry)", info.stream, _logger,
@@ -2847,7 +2911,7 @@ namespace Ice
 
                     case IceInternal.Protocol.requestBatchMsg:
                     {
-                        if(_state == StateClosing)
+                        if(_state >= StateClosing)
                         {
                             IceInternal.TraceUtil.trace("received batch request during closing\n" +
                                                         "(ignored by server, client will retry)", info.stream, _logger,
@@ -2878,6 +2942,7 @@ namespace Ice
                         {
                             _requests.Remove(info.requestId);
                             og.finished(info.stream);
+                            _m.NotifyAll(); // Notify threads blocked in close(false)
                         }
                         else if(_asyncRequests.TryGetValue(info.requestId, out info.outAsync))
                         {
@@ -2900,8 +2965,8 @@ namespace Ice
                             {
                                 ++_dispatchCount;
                             }
+                            _m.NotifyAll(); // Notify threads blocked in close(false)
                         }
-                        _m.NotifyAll(); // Notify threads blocked in close(false)
                         break;
                     }
 
@@ -2938,6 +3003,8 @@ namespace Ice
                     setState(StateClosed, ex);
                 }
             }
+
+            return _state == StateHolding ? IceInternal.SocketOperation.None : IceInternal.SocketOperation.Read;
         }
 
         private void invokeAll(IceInternal.BasicStream stream, int invokeNum, int requestId, byte compress,
@@ -2957,6 +3024,8 @@ namespace Ice
                     // Prepare the invocation.
                     //
                     bool response = !_endpoint.datagram() && requestId != 0;
+                    Debug.Assert(!response || invokeNum == 1);
+
                     inc = getIncoming(adapter, response, compress, requestId);
 
                     //
@@ -2985,8 +3054,42 @@ namespace Ice
             }
         }
 
-        private void scheduleTimeout(int status, int timeout)
+        private void scheduleTimeout(int status)
         {
+            int timeout;
+            if(_state < StateActive)
+            {
+                IceInternal.DefaultsAndOverrides defaultsAndOverrides = _instance.defaultsAndOverrides();
+                if(defaultsAndOverrides.overrideConnectTimeout)
+                {
+                    timeout = defaultsAndOverrides.overrideConnectTimeoutValue;
+                }
+                else
+                {
+                    timeout = _endpoint.timeout();
+                }
+            }
+            else if(_state < StateClosingPending)
+            {
+                if(_readHeader) // No timeout for reading the header.
+                {
+                    status &= ~IceInternal.SocketOperation.Read;
+                }
+                timeout = _endpoint.timeout();
+            }
+            else
+            {
+                IceInternal.DefaultsAndOverrides defaultsAndOverrides = _instance.defaultsAndOverrides();
+                if(defaultsAndOverrides.overrideCloseTimeout)
+                {
+                    timeout = defaultsAndOverrides.overrideCloseTimeoutValue;
+                }
+                else
+                {
+                    timeout = _endpoint.timeout();
+                }
+            }
+
             if(timeout < 0)
             {
                 return;
@@ -2994,11 +3097,19 @@ namespace Ice
 
             if((status & IceInternal.SocketOperation.Read) != 0)
             {
+                if(_readTimeoutScheduled)
+                {
+                    _timer.cancel(_readTimeout);
+                }
                 _timer.schedule(_readTimeout, timeout);
                 _readTimeoutScheduled = true;
             }
             if((status & (IceInternal.SocketOperation.Write | IceInternal.SocketOperation.Connect)) != 0)
             {
+                if(_writeTimeoutScheduled)
+                {
+                    _timer.cancel(_writeTimeout);
+                }
                 _timer.schedule(_writeTimeout, timeout);
                 _writeTimeoutScheduled = true;
             }
@@ -3012,39 +3123,13 @@ namespace Ice
                 _readTimeoutScheduled = false;
             }
             if((status & (IceInternal.SocketOperation.Write | IceInternal.SocketOperation.Connect)) != 0 &&
-                _writeTimeoutScheduled)
+               _writeTimeoutScheduled)
             {
                 _timer.cancel(_writeTimeout);
                 _writeTimeoutScheduled = false;
             }
         }
 
-        private int connectTimeout()
-        {
-            IceInternal.DefaultsAndOverrides defaultsAndOverrides = _instance.defaultsAndOverrides();
-            if(defaultsAndOverrides.overrideConnectTimeout)
-            {
-                return defaultsAndOverrides.overrideConnectTimeoutValue;
-            }
-            else
-            {
-                return _endpoint.timeout();
-            }
-        }
-
-        private int closeTimeout()
-        {
-            IceInternal.DefaultsAndOverrides defaultsAndOverrides = _instance.defaultsAndOverrides();
-            if(defaultsAndOverrides.overrideCloseTimeout)
-            {
-                return defaultsAndOverrides.overrideCloseTimeoutValue;
-            }
-            else
-            {
-                return _endpoint.timeout();
-            }
-        }
-
         private ConnectionInfo initConnectionInfo()
         {
             if(_info != null)
@@ -3085,43 +3170,47 @@ namespace Ice
             _logger.warning(msg + ":\n" + ex + "\n" + _transceiver.ToString());
         }
 
-        private void observerStartRead(int pos)
+        private void observerStartRead(IceInternal.Buffer buf)
         {
             if(_readStreamPos >= 0)
             {
-                _observer.receivedBytes(pos - _readStreamPos);
+                Debug.Assert(!buf.empty());
+                _observer.receivedBytes(buf.b.position() - _readStreamPos);
             }
-            _readStreamPos = pos;
+            _readStreamPos = buf.empty() ? -1 : buf.b.position();
         }
 
-        private void observerFinishRead(int pos)
+        private void observerFinishRead(IceInternal.Buffer buf)
         {
             if(_readStreamPos == -1)
             {
                 return;
             }
-            Debug.Assert(pos >= _readStreamPos);
-            _observer.receivedBytes(pos - _readStreamPos);
+            Debug.Assert(buf.b.position() >= _readStreamPos);
+            _observer.receivedBytes(buf.b.position() - _readStreamPos);
             _readStreamPos = -1;
         }
 
-        private void observerStartWrite(int pos)
+        private void observerStartWrite(IceInternal.Buffer buf)
         {
             if(_writeStreamPos >= 0)
             {
-                _observer.sentBytes(pos - _writeStreamPos);
+                Debug.Assert(!buf.empty());
+                _observer.sentBytes(buf.b.position() - _writeStreamPos);
             }
-            _writeStreamPos = pos;
+            _writeStreamPos = buf.empty() ? -1 : buf.b.position();
         }
 
-        private void observerFinishWrite(int pos)
+        private void observerFinishWrite(IceInternal.Buffer buf)
         {
             if(_writeStreamPos == -1)
             {
                 return;
             }
-            Debug.Assert(pos >= _writeStreamPos);
-            _observer.sentBytes(pos - _writeStreamPos);
+            if(buf.b.position() > _writeStreamPos)
+            {
+                _observer.sentBytes(buf.b.position() - _writeStreamPos);
+            }
             _writeStreamPos = -1;
         }
 
@@ -3251,9 +3340,9 @@ namespace Ice
 
             internal void timedOut()
             {
-                Debug.Assert(this.@out != null || this.outAsync != null);
-                this.@out = null;
-                this.outAsync = null;
+                Debug.Assert((@out != null || outAsync != null) && !isSent);
+                @out = null;
+                outAsync = null;
             }
 
             internal void adopt()
@@ -3268,7 +3357,7 @@ namespace Ice
                 }
             }
 
-            internal bool sent(ConnectionI connection)
+            internal bool sent()
             {
                 isSent = true; // The message is sent.
 
@@ -3280,7 +3369,7 @@ namespace Ice
                 else if(outAsync != null)
                 {
                     sentCallback = outAsync.sent__();
-                    return sentCallback != null;
+                    return sentCallback != null || replyOutAsync != null;
                 }
                 else
                 {
@@ -3395,6 +3484,7 @@ namespace Ice
             ConnectionState.ConnectionStateActive,       // StateActive
             ConnectionState.ConnectionStateHolding,      // StateHolding
             ConnectionState.ConnectionStateClosing,      // StateClosing
+            ConnectionState.ConnectionStateClosing,      // StateClosingPending
             ConnectionState.ConnectionStateClosed,       // StateClosed
             ConnectionState.ConnectionStateClosed,       // StateFinished
         };
diff --git a/cs/src/Ice/EndpointFactory.cs b/cs/src/Ice/EndpointFactory.cs
index 4de8bd7f76c..7f2712b850e 100644
--- a/cs/src/Ice/EndpointFactory.cs
+++ b/cs/src/Ice/EndpointFactory.cs
@@ -9,14 +9,17 @@
 
 namespace IceInternal
 {
+    using System.Collections.Generic;
 
     public interface EndpointFactory
     {
         short type();
         string protocol();
-        EndpointI create(string str, bool oaEndpoint);
+        EndpointI create(List<string> args, bool oaEndpoint);
         EndpointI read(BasicStream s);
         void destroy();
+
+        EndpointFactory clone(ProtocolInstance instance);
     }
 
 }
diff --git a/cs/src/Ice/EndpointFactoryManager.cs b/cs/src/Ice/EndpointFactoryManager.cs
index 789515e91a7..d9f1c79bbeb 100644
--- a/cs/src/Ice/EndpointFactoryManager.cs
+++ b/cs/src/Ice/EndpointFactoryManager.cs
@@ -21,7 +21,7 @@ namespace IceInternal
             instance_ = instance;
             _factories = new List<EndpointFactory>();
         }
-        
+
         public void add(EndpointFactory factory)
         {
             lock(this)
@@ -37,7 +37,7 @@ namespace IceInternal
                 _factories.Add(factory);
             }
         }
-        
+
         public EndpointFactory get(short type)
         {
             lock(this)
@@ -53,104 +53,138 @@ namespace IceInternal
                 return null;
             }
         }
-        
+
         public EndpointI create(string str, bool oaEndpoint)
         {
+            string[] arr = IceUtilInternal.StringUtil.splitString(str, " \t\r\n");
+            if(arr == null)
+            {
+                Ice.EndpointParseException e = new Ice.EndpointParseException();
+                e.str = "mismatched quote";
+                throw e;
+            }
+
+            if(arr.Length == 0)
+            {
+                Ice.EndpointParseException e = new Ice.EndpointParseException();
+                e.str = "value has no non-whitespace characters";
+                throw e;
+            }
+
+            List<string> v = new List<string>(arr);
+            string protocol = v[0];
+            v.RemoveAt(0);
+
+            if(protocol.Equals("default"))
+            {
+                protocol = instance_.defaultsAndOverrides().defaultProtocol;
+            }
+
+            EndpointFactory factory = null;
+
             lock(this)
             {
-                string s = str.Trim();
-                if(s.Length == 0)
-                {
-                    Ice.EndpointParseException e = new Ice.EndpointParseException();
-                    e.str = "value has no non-whitespace characters";
-                    throw e;
-                }
-                
-                Regex p = new Regex("([ \t\n\r]+)|$");
-                Match m = p.Match(s);
-                Debug.Assert(m.Success);
-                
-                string protocol = s.Substring(0, m.Index);
-                
-                if(protocol.Equals("default"))
-                {
-                    protocol = instance_.defaultsAndOverrides().defaultProtocol;
-                }
-                
                 for(int i = 0; i < _factories.Count; i++)
                 {
-                    EndpointFactory f = (EndpointFactory)_factories[i];
+                    EndpointFactory f = _factories[i];
                     if(f.protocol().Equals(protocol))
                     {
-                        return f.create(s.Substring(m.Index + m.Length), oaEndpoint);
-
-                        // Code below left in place for debugging.
-
-                        /*
-                        EndpointI e = f.create(s.Substring(m.Index + m.Length), oaEndpoint);
-                        BasicStream bs = new BasicStream(instance_, true);
-                        e.streamWrite(bs);
-                        Buffer buf = bs.getBuffer();
-                        buf.b.position(0);
-                        short type = bs.readShort();
-                        EndpointI ue = new IceInternal.OpaqueEndpointI(type, bs);
-                        System.Console.Error.WriteLine("Normal: " + e);
-                        System.Console.Error.WriteLine("Opaque: " + ue);
-                        return e;
-                        */
+                        factory = f;
                     }
                 }
+            }
 
-                //
-                // If the stringified endpoint is opaque, create an unknown endpoint,
-                // then see whether the type matches one of the known endpoints.
-                //
-                if(protocol.Equals("opaque"))
+            if(factory != null)
+            {
+                EndpointI e = factory.create(v, oaEndpoint);
+                if(v.Count > 0)
                 {
-                    EndpointI ue = new OpaqueEndpointI(s.Substring(m.Index + m.Length));
-                    for(int i = 0; i < _factories.Count; i++)
-                    {
-                        EndpointFactory f = (EndpointFactory)_factories[i];
-                        if(f.type() == ue.type())
-                        {
-                            //
-                            // Make a temporary stream, write the opaque endpoint data into the stream,
-                            // and ask the factory to read the endpoint data from that stream to create
-                            // the actual endpoint.
-                            //
-                            BasicStream bs = new BasicStream(instance_, Ice.Util.currentProtocolEncoding, true);
-                            ue.streamWrite(bs);
-                            Buffer buf = bs.getBuffer();
-                            buf.b.position(0);
-                            bs.readShort(); // type
-                            return f.read(bs);
-                        }
-                    }
-                    return ue; // Endpoint is opaque, but we don't have a factory for its type.
+                    Ice.EndpointParseException ex = new Ice.EndpointParseException();
+                    ex.str = "unrecognized argument `" + v[0] + "' in endpoint `" + str + "'";
+                    throw ex;
                 }
-                return null;
+                return e;
+
+                // Code below left in place for debugging.
+
+                /*
+                EndpointI e = f.create(s.Substring(m.Index + m.Length), oaEndpoint);
+                BasicStream bs = new BasicStream(instance_, true);
+                e.streamWrite(bs);
+                Buffer buf = bs.getBuffer();
+                buf.b.position(0);
+                short type = bs.readShort();
+                EndpointI ue = new IceInternal.OpaqueEndpointI(type, bs);
+                System.Console.Error.WriteLine("Normal: " + e);
+                System.Console.Error.WriteLine("Opaque: " + ue);
+                return e;
+                */
+            }
+
+            //
+            // If the stringified endpoint is opaque, create an unknown endpoint,
+            // then see whether the type matches one of the known endpoints.
+            //
+            if(protocol.Equals("opaque"))
+            {
+                EndpointI ue = new OpaqueEndpointI(v);
+                if(v.Count > 0)
+                {
+                    Ice.EndpointParseException ex = new Ice.EndpointParseException();
+                    ex.str = "unrecognized argument `" + v[0] + "' in endpoint `" + str + "'";
+                    throw ex;
+                }
+                factory = get(ue.type());
+                if(factory != null)
+                {
+                    //
+                    // Make a temporary stream, write the opaque endpoint data into the stream,
+                    // and ask the factory to read the endpoint data from that stream to create
+                    // the actual endpoint.
+                    //
+                    BasicStream bs = new BasicStream(instance_, Ice.Util.currentProtocolEncoding, true);
+                    bs.writeShort(ue.type());
+                    ue.streamWrite(bs);
+                    Buffer buf = bs.getBuffer();
+                    buf.b.position(0);
+                    bs.readShort(); // type
+                    bs.startReadEncaps();
+                    EndpointI e = factory.read(bs);
+                    bs.endReadEncaps();
+                    return e;
+                }
+                return ue; // Endpoint is opaque, but we don't have a factory for its type.
             }
+
+            return null;
         }
-        
+
         public EndpointI read(BasicStream s)
         {
             lock(this)
             {
                 short type = s.readShort();
-                
-                for(int i = 0; i < _factories.Count; i++)
+
+                EndpointFactory factory = get(type);
+                EndpointI e = null;
+
+                s.startReadEncaps();
+
+                if(factory != null)
                 {
-                    EndpointFactory f = (EndpointFactory)_factories[i];
-                    if(f.type() == type)
-                    {
-                        return f.read(s);
-                    }
+                    e = factory.read(s);
                 }
-                
-                return new OpaqueEndpointI(type, s);
+                else
+                {
+                    e = new OpaqueEndpointI(type, s);
+                }
+
+                s.endReadEncaps();
+
+                return e;
             }
         }
-        
+
         internal void destroy()
         {
             for(int i = 0; i < _factories.Count; i++)
@@ -160,7 +194,7 @@ namespace IceInternal
             }
             _factories.Clear();
         }
-        
+
         private readonly Instance instance_;
         private readonly List<EndpointFactory> _factories;
     }
diff --git a/cs/src/Ice/EndpointHostResolver.cs b/cs/src/Ice/EndpointHostResolver.cs
index e2750091303..5b2a14d1d5d 100644
--- a/cs/src/Ice/EndpointHostResolver.cs
+++ b/cs/src/Ice/EndpointHostResolver.cs
@@ -38,7 +38,7 @@ namespace IceInternal
         }
 
         
-        public List<Connector> resolve(string host, int port, Ice.EndpointSelectionType selType, EndpointI endpoint)
+        public List<Connector> resolve(string host, int port, Ice.EndpointSelectionType selType, IPEndpointI endpoint)
         {
             //
             // Try to get the addresses without DNS lookup. If this doesn't
@@ -95,7 +95,7 @@ namespace IceInternal
             return connectors;
         }
 
-        public void resolve(string host, int port, Ice.EndpointSelectionType selType, EndpointI endpoint, 
+        public void resolve(string host, int port, Ice.EndpointSelectionType selType, IPEndpointI endpoint,
                             EndpointI_connectors callback)
         {
             //
@@ -296,7 +296,7 @@ namespace IceInternal
             internal string host;
             internal int port;
             internal Ice.EndpointSelectionType selType;
-            internal EndpointI endpoint;
+            internal IPEndpointI endpoint;
             internal EndpointI_connectors callback;
             internal Ice.Instrumentation.Observer observer;
         }
diff --git a/cs/src/Ice/EndpointI.cs b/cs/src/Ice/EndpointI.cs
index 762438d48fd..a83bda53756 100644
--- a/cs/src/Ice/EndpointI.cs
+++ b/cs/src/Ice/EndpointI.cs
@@ -22,22 +22,24 @@ namespace IceInternal
     }
 
     public abstract class EndpointI : Ice.Endpoint, System.IComparable<EndpointI>
-    {    
-        public EndpointI(string connectionId)
-        {
-            connectionId_ = connectionId;
-        }
-
-        public EndpointI()
+    {
+        public override string ToString()
         {
+            return ice_toString_();
         }
 
-        public override string ToString()
+        public virtual string ice_toString_()
         {
-            return ice_toString_();
+            //
+            // WARNING: Certain features, such as proxy validation in Glacier2,
+            // depend on the format of proxy strings. Changes to toString() and
+            // methods called to generate parts of the reference string could break
+            // these features. Please review for all features that depend on the
+            // format of proxyToString() before changing this and related code.
+            //
+            return protocol() + options();
         }
 
-        public abstract string ice_toString_();
         public abstract Ice.EndpointInfo getInfo();
 
         public override bool Equals(object obj)
@@ -49,20 +51,9 @@ namespace IceInternal
             return CompareTo((EndpointI)obj) == 0;
         }
 
-        public override int GetHashCode()
-        {
-            int h = 5381;
-            IceInternal.HashUtil.hashAdd(ref h, connectionId_);
-            return h;
-        }
-
-        public virtual int CompareTo(EndpointI p)
+        public override int GetHashCode() // Avoids a compiler warning.
         {
-            if(!connectionId_.Equals(p.connectionId_))
-            {
-                return string.Compare(connectionId_, p.connectionId_, StringComparison.Ordinal);
-            }
-
+            Debug.Assert(false);
             return 0;
         }
 
@@ -95,6 +86,11 @@ namespace IceInternal
         public abstract EndpointI timeout(int t);
 
         //
+        // Return the connection ID.
+        //
+        public abstract string connectionId();
+
+        //
         // Return a new endpoint with a different connection id.
         //
         public abstract EndpointI connectionId(string connectionId);
@@ -116,21 +112,13 @@ namespace IceInternal
         // Return true if the endpoint is datagram-based.
         //
         public abstract bool datagram();
-        
+
         //
         // Return true if the endpoint is secure.
         //
         public abstract bool secure();
 
         //
-        // Return the connection ID.
-        //
-        public string connectionId()
-        {
-            return connectionId_;
-        }
-
-        //
         // Return a server side transceiver for this endpoint, or null if a
         // transceiver can only be created by an acceptor. In case a
         // transceiver is created, this operation also returns a new
@@ -161,21 +149,68 @@ namespace IceInternal
         // was specified on client side.
         //
         public abstract List<EndpointI> expand();
- 
+
         //
         // Check whether the endpoint is equivalent to another one.
         //
         public abstract bool equivalent(EndpointI endpoint);
 
-        public virtual List<Connector> connectors(List<EndPoint> addresses, NetworkProxy proxy)
+        public abstract int CompareTo(EndpointI obj);
+
+        public abstract string options();
+
+        public virtual void initWithOptions(List<string> args)
         {
-            Debug.Assert(false);
-            return null;
+            List<string> unknown = new List<string>();
+
+            string str = "`" + protocol() + " ";
+            foreach(string p in args)
+            {
+                if(IceUtilInternal.StringUtil.findFirstOf(p, " \t\n\r") != -1)
+                {
+                    str += " \"" + p + "\"";
+                }
+                else
+                {
+                    str += " " + p;
+                }
+            }
+            str += "'";
+
+            for(int n = 0; n < args.Count; ++n)
+            {
+                string option = args[n];
+                if(option.Length < 2 || option[0] != '-')
+                {
+                    unknown.Add(option);
+                    continue;
+                }
+
+                string argument = null;
+                if(n + 1 < args.Count && args[n + 1][0] != '-')
+                {
+                    argument = args[++n];
+                }
+
+                if(!checkOption(option, argument, str))
+                {
+                    unknown.Add(option);
+                    if(argument != null)
+                    {
+                        unknown.Add(argument);
+                    }
+                }
+            }
+
+            args.Clear();
+            args.AddRange(unknown);
         }
 
-        protected Ice.ProtocolVersion protocol_;
-        protected Ice.EncodingVersion encoding_;
-        protected string connectionId_ = "";
+        protected virtual bool checkOption(string option, string argument, string endpoint)
+        {
+            // Must be overridden to check for options.
+            return false;
+        }
     }
 
 }
diff --git a/cs/src/Ice/EventHandler.cs b/cs/src/Ice/EventHandler.cs
index eeb2264f4bd..5ef8f6bffdd 100644
--- a/cs/src/Ice/EventHandler.cs
+++ b/cs/src/Ice/EventHandler.cs
@@ -36,6 +36,7 @@ public abstract class EventHandler
     internal int _started = 0;
     internal bool _finish = false;
     
+    internal bool _hasMoreData = false;
     internal int _registered = 0;
 }
 
diff --git a/cs/src/Ice/IPEndpointI.cs b/cs/src/Ice/IPEndpointI.cs
new file mode 100644
index 00000000000..d0857da9068
--- /dev/null
+++ b/cs/src/Ice/IPEndpointI.cs
@@ -0,0 +1,366 @@
+// **********************************************************************
+//
+// Copyright (c) 2003-2014 ZeroC, Inc. All rights reserved.
+//
+// This copy of Ice is licensed to you under the terms described in the
+// ICE_LICENSE file included in this distribution.
+//
+// **********************************************************************
+
+namespace IceInternal
+{
+
+    using System.Collections.Generic;
+    using System.Diagnostics;
+    using System.Globalization;
+    using System.Net;
+    using System;
+
+    public abstract class IPEndpointI : EndpointI
+    {
+        public IPEndpointI(ProtocolInstance instance, string host, int port, string connectionId)
+        {
+            instance_ = instance;
+            host_ = host;
+            port_ = port;
+            connectionId_ = connectionId;
+            _hashInitialized = false;
+        }
+
+        public IPEndpointI(ProtocolInstance instance)
+        {
+            instance_ = instance;
+            host_ = null;
+            port_ = 0;
+            connectionId_ = "";
+            _hashInitialized = false;
+        }
+
+        public IPEndpointI(ProtocolInstance instance, BasicStream s)
+        {
+            instance_ = instance;
+            host_ = s.readString();
+            port_ = s.readInt();
+            connectionId_ = "";
+            _hashInitialized = false;
+        }
+
+        private sealed class InfoI : Ice.IPEndpointInfo
+        {
+            public InfoI(IPEndpointI e)
+            {
+                _endpoint = e;
+            }
+
+            override public short type()
+            {
+                return _endpoint.type();
+            }
+
+            override public bool datagram()
+            {
+                return _endpoint.datagram();;
+            }
+
+            override public bool secure()
+            {
+                return _endpoint.secure();
+            }
+
+            private IPEndpointI _endpoint;
+        }
+
+        public override Ice.EndpointInfo getInfo()
+        {
+            InfoI info = new InfoI(this);
+            fillEndpointInfo(info);
+            return info;
+        }
+
+        public override void streamWrite(BasicStream s)
+        {
+            s.startWriteEncaps();
+            streamWriteImpl(s);
+            s.endWriteEncaps();
+        }
+
+        public override short type()
+        {
+            return instance_.type();
+        }
+
+        public override string protocol()
+        {
+            return instance_.protocol();
+        }
+
+        public override string connectionId()
+        {
+            return connectionId_;
+        }
+
+        public override EndpointI connectionId(string connectionId)
+        {
+            if(connectionId.Equals(connectionId_))
+            {
+                return this;
+            }
+            else
+            {
+                return createEndpoint(host_, port_, connectionId);
+            }
+        }
+
+        public override List<Connector> connectors(Ice.EndpointSelectionType selType)
+        {
+#if SILVERLIGHT
+            return connectors(Network.getAddresses(host_,
+                                                   port_,
+                                                   instance_.protocolSupport(),
+                                                   selType,
+                                                   instance_.preferIPv6(),
+                                                   false),
+                              instance_.networkProxy());
+#else
+            return instance_.resolve(host_, port_, selType, this);
+#endif
+        }
+
+        public override void connectors_async(Ice.EndpointSelectionType selType, EndpointI_connectors callback)
+        {
+#if SILVERLIGHT
+            callback.connectors(connectors(selType));
+#else
+            instance_.resolve(host_, port_, selType, this, callback);
+#endif
+        }
+
+        public override List<EndpointI> expand()
+        {
+            List<EndpointI> endps = new List<EndpointI>();
+            List<string> hosts = Network.getHostsForEndpointExpand(host_, instance_.protocolSupport(), false);
+            if(hosts == null || hosts.Count == 0)
+            {
+                endps.Add(this);
+            }
+            else
+            {
+                foreach(string h in hosts)
+                {
+                    endps.Add(createEndpoint(h, port_, connectionId_));
+                }
+            }
+            return endps;
+        }
+
+        public override bool equivalent(EndpointI endpoint)
+        {
+            if(!(endpoint is IPEndpointI))
+            {
+                return false;
+            }
+            IPEndpointI ipEndpointI = (IPEndpointI)endpoint;
+            return ipEndpointI.type() == type() && ipEndpointI.host_.Equals(host_) && ipEndpointI.port_ == port_;
+        }
+
+        public virtual List<Connector> connectors(List<EndPoint> addresses, NetworkProxy proxy)
+        {
+            List<Connector> connectors = new List<Connector>();
+            foreach(EndPoint p in addresses)
+            {
+                connectors.Add(createConnector(p, proxy));
+            }
+            return connectors;
+        }
+
+        public override string options()
+        {
+            //
+            // WARNING: Certain features, such as proxy validation in Glacier2,
+            // depend on the format of proxy strings. Changes to toString() and
+            // methods called to generate parts of the reference string could break
+            // these features. Please review for all features that depend on the
+            // format of proxyToString() before changing this and related code.
+            //
+            string s = "";
+
+            if(host_ != null && host_.Length > 0)
+            {
+                s += " -h ";
+                bool addQuote = host_.IndexOf(':') != -1;
+                if(addQuote)
+                {
+                    s += "\"";
+                }
+                s += host_;
+                if(addQuote)
+                {
+                    s += "\"";
+                }
+            }
+
+            s += " -p " + port_;
+
+            return s;
+        }
+
+        public override int GetHashCode()
+        {
+            if(!_hashInitialized)
+            {
+                _hashValue = 5381;
+                HashUtil.hashAdd(ref _hashValue, type());
+                hashInit(ref _hashValue);
+                _hashInitialized = true;
+            }
+            return _hashValue;
+        }
+
+        public override int CompareTo(EndpointI obj)
+        {
+            if(!(obj is IPEndpointI))
+            {
+                return type() < obj.type() ? -1 : 1;
+            }
+
+            IPEndpointI p = (IPEndpointI)obj;
+            if(this == p)
+            {
+                return 0;
+            }
+
+            int v = string.Compare(host_, p.host_, StringComparison.Ordinal);
+            if(v != 0)
+            {
+                return v;
+            }
+
+            if(port_ < p.port_)
+            {
+                return -1;
+            }
+            else if(p.port_ < port_)
+            {
+                return 1;
+            }
+
+            return string.Compare(connectionId_, p.connectionId_, StringComparison.Ordinal);
+        }
+
+        public string host()
+        {
+            return host_;
+        }
+
+        public int port()
+        {
+            return port_;
+        }
+
+        protected virtual void streamWriteImpl(BasicStream s)
+        {
+            s.writeString(host_);
+            s.writeInt(port_);
+        }
+
+        protected virtual void hashInit(ref int h)
+        {
+            HashUtil.hashAdd(ref h, host_);
+            HashUtil.hashAdd(ref h, port_);
+            HashUtil.hashAdd(ref h, connectionId_);
+        }
+
+        protected virtual void fillEndpointInfo(Ice.IPEndpointInfo info)
+        {
+            info.host = host_;
+            info.port = port_;
+        }
+
+        public void initWithOptions(List<string> args, bool oaEndpoint)
+        {
+            base.initWithOptions(args);
+
+            if(host_ == null || host_.Length == 0)
+            {
+                host_ = instance_.defaultHost();
+            }
+            else if(host_.Equals("*"))
+            {
+                if(oaEndpoint)
+                {
+                    host_ = "";
+                }
+                else
+                {
+                    throw new Ice.EndpointParseException("`-h *' not valid for proxy endpoint `" + ToString() + "'");
+                }
+            }
+
+            if(host_ == null)
+            {
+                host_ = "";
+            }
+        }
+
+        protected override bool checkOption(string option, string argument, string endpoint)
+        {
+            switch(option[1])
+            {
+                case 'h':
+                {
+                    if(argument == null)
+                    {
+                        throw new Ice.EndpointParseException("no argument provided for -h option in endpoint " +
+                                                             endpoint);
+                    }
+                    host_ = argument;
+                    return true;
+                }
+
+                case 'p':
+                {
+                    if(argument == null)
+                    {
+                        throw new Ice.EndpointParseException("no argument provided for -p option in endpoint " +
+                                                             endpoint);
+                    }
+
+                    try
+                    {
+                        port_ = System.Int32.Parse(argument, CultureInfo.InvariantCulture);
+                    }
+                    catch(System.FormatException ex)
+                    {
+                        Ice.EndpointParseException e = new Ice.EndpointParseException(ex);
+                        e.str = "invalid port value `" + argument + "' in endpoint " + endpoint;
+                        throw e;
+                    }
+
+                    if(port_ < 0 || port_ > 65535)
+                    {
+                        throw new Ice.EndpointParseException("port value `" + argument +
+                                                             "' out of range in endpoint " + endpoint);
+                    }
+
+                    return true;
+                }
+
+                default:
+                {
+                    return false;
+                }
+            }
+        }
+
+        protected abstract Connector createConnector(EndPoint addr, NetworkProxy proxy);
+        protected abstract IPEndpointI createEndpoint(string host, int port, string connectionId);
+
+        protected ProtocolInstance instance_;
+        protected string host_;
+        protected int port_;
+        protected string connectionId_;
+        private bool _hashInitialized;
+        private int _hashValue;
+    }
+
+}
diff --git a/cs/src/Ice/Instance.cs b/cs/src/Ice/Instance.cs
index 222941ae09d..abcc4cab4e3 100644
--- a/cs/src/Ice/Instance.cs
+++ b/cs/src/Ice/Instance.cs
@@ -829,9 +829,13 @@ namespace IceInternal
                 }
 
                 _endpointFactoryManager = new EndpointFactoryManager(this);
-                EndpointFactory tcpEndpointFactory = new TcpEndpointFactory(this);
+                ProtocolInstance tcpProtocolInstance =
+                    new ProtocolInstance(this, Ice.TCPEndpointType.value, "tcp");
+                EndpointFactory tcpEndpointFactory = new TcpEndpointFactory(tcpProtocolInstance);
                 _endpointFactoryManager.add(tcpEndpointFactory);
-                EndpointFactory udpEndpointFactory = new UdpEndpointFactory(this);
+                ProtocolInstance udpProtocolInstance =
+                    new ProtocolInstance(this, Ice.UDPEndpointType.value, "udp");
+                EndpointFactory udpEndpointFactory = new UdpEndpointFactory(udpProtocolInstance);
                 _endpointFactoryManager.add(udpEndpointFactory);
 
 #if !SILVERLIGHT
diff --git a/cs/src/Ice/Makefile b/cs/src/Ice/Makefile
index b6b312eed25..a943404d4bd 100644
--- a/cs/src/Ice/Makefile
+++ b/cs/src/Ice/Makefile
@@ -51,6 +51,7 @@ SRCS		= Acceptor.cs \
 		  Incoming.cs \
 		  Instance.cs \
 		  InstrumentationI.cs \
+		  IPEndpointI.cs \
 		  LocatorInfo.cs \
 		  LoggerI.cs \
 		  LoggerPlugin.cs \
@@ -77,6 +78,7 @@ SRCS		= Acceptor.cs \
 		  Property.cs \
 		  PropertyNames.cs \
 		  Protocol.cs \
+		  ProtocolInstance.cs \
 		  ProtocolPluginFacade.cs \
 		  Proxy.cs \
 		  ProxyFactory.cs \
diff --git a/cs/src/Ice/Makefile.mak b/cs/src/Ice/Makefile.mak
index e4685bd1b0f..9108c1ed643 100644
--- a/cs/src/Ice/Makefile.mak
+++ b/cs/src/Ice/Makefile.mak
@@ -52,6 +52,7 @@ SRCS		= Acceptor.cs \
 		  Incoming.cs \
 		  Instance.cs \
 		  InstrumentationI.cs \
+		  IPEndpointI.cs \
 		  LocatorInfo.cs \
 		  LoggerI.cs \
 		  LoggerPlugin.cs \
@@ -78,6 +79,7 @@ SRCS		= Acceptor.cs \
 		  Property.cs \
 		  PropertyNames.cs \
 		  Protocol.cs \
+		  ProtocolInstance.cs \
 		  ProtocolPluginFacade.cs \
 		  Proxy.cs \
 		  ProxyFactory.cs \
diff --git a/cs/src/Ice/OpaqueEndpointI.cs b/cs/src/Ice/OpaqueEndpointI.cs
index f1666e75bd9..0dd57e0cac8 100644
--- a/cs/src/Ice/OpaqueEndpointI.cs
+++ b/cs/src/Ice/OpaqueEndpointI.cs
@@ -16,162 +16,47 @@ namespace IceInternal
 
     sealed class OpaqueEndpointI : EndpointI
     {
-        public OpaqueEndpointI(string str) : base("")
+        public OpaqueEndpointI(List<string> args)
         {
+            _type = -1;
             _rawEncoding = Ice.Util.Encoding_1_0;
+            _rawBytes = new byte[0];
 
-            int topt = 0;
-            int vopt = 0;
+            initWithOptions(args);
 
-            char[] separators = { ' ', '\t', '\n', '\r' };
-            string[] arr = str.Split(separators);
-
-            int i = 0;
-            while(i < arr.Length)
+            if(_type < 0)
             {
-                if(arr[i].Length == 0)
-                {
-                    i++;
-                    continue;
-                }
-
-                string option = arr[i++];
-                if(option.Length != 2 || option[0] != '-')
-                {
-                    throw new Ice.EndpointParseException("expected an endpoint option but found `" + option +
-                                                         "' in endpoint `opaque " + str + "'");
-                }
-
-                string argument = null;
-                if(i < arr.Length && arr[i][0] != '-')
-                {
-                    argument = arr[i++];
-                }
-
-                switch(option[1])
-                {
-                    case 't':
-                    {
-                        if(argument == null)
-                        {
-                            throw new Ice.EndpointParseException(
-                                "no argument provided for -t option in endpoint `opaque " + str + "'");
-                        }
-
-                        int t;
-                        try
-                        {
-                            t = System.Int32.Parse(argument, CultureInfo.InvariantCulture);
-                        }
-                        catch(System.FormatException)
-                        {
-                            throw new Ice.EndpointParseException("invalid timeout value `" + argument +
-                                                                 "' in endpoint `opaque " + str + "'");
-                        }
-
-                        if(t < 0 || t > 65535)
-                        {
-                            throw new Ice.EndpointParseException("timeout value `" + argument +
-                                                                 "' out of range in endpoint `opaque " + str + "'");
-                        }
-
-                        _type = (short)t;
-                        ++topt;
-                        if(topt > 1)
-                        {
-                            throw new Ice.EndpointParseException("multiple -t options in endpoint `opaque " + str +
-                                                                 "'");
-                        }
-                        break;
-                    }
-
-                    case 'e':
-                    {
-                        if(argument == null)
-                        {
-                            throw new Ice.EndpointParseException(
-                                "no argument provided for -e option in endpoint `opaque " + str + "'");
-                        }
-                        
-                        try
-                        {
-                            _rawEncoding = Ice.Util.stringToEncodingVersion(argument);
-                        }
-                        catch(Ice.VersionParseException e)
-                        {
-                            throw new Ice.EndpointParseException("invalid encoding version `" + argument + 
-                                                                 "' in endpoint `opaque " + str + "':\n" + e.str);
-                        }
-                        break;
-                    }
-                    
-                    case 'v':
-                    {
-                        if(argument == null)
-                        {
-                            throw new Ice.EndpointParseException(
-                                "no argument provided for -v option in endpoint `opaque " + str + "'");
-                        }
-                        for(int j = 0; j < argument.Length; ++j)
-                        {
-                            if(!IceUtilInternal.Base64.isBase64(argument[j]))
-                            {
-                                throw new Ice.EndpointParseException(
-                                    "invalid base64 character `" + argument[j] + "' (ordinal " +
-                                    ((int)argument[j]) + ") in endpoint `opaque " + str + "'");
-                            }
-                        }
-                        _rawBytes = IceUtilInternal.Base64.decode(argument);
-                        ++vopt;
-                        if(vopt > 1)
-                        {
-                            throw new Ice.EndpointParseException("multiple -v options in endpoint `opaque " + str +
-                                                                 "'");
-                        }
-                        break;
-                    }
-
-                    default:
-                    {
-                        throw new Ice.EndpointParseException("invalid option `" + option + "' in endpoint `opaque " +
-                                                              str + "'");
-                    }
-                }
-            }
-
-            if(topt != 1)
-            {
-                throw new Ice.EndpointParseException("no -t option in endpoint `opaque " + str + "'");
+                throw new Ice.EndpointParseException("no -t option in endpoint " + ToString());
             }
-            if(vopt != 1)
+            if(_rawBytes.Length == 0)
             {
-                throw new Ice.EndpointParseException("no -v option in endpoint `opaque " + str + "'");
+                throw new Ice.EndpointParseException("no -v option in endpoint " + ToString());
             }
+
             calcHashValue();
         }
 
         public OpaqueEndpointI(short type, BasicStream s)
         {
             _type = type;
-            _rawEncoding = s.startReadEncaps();
+            _rawEncoding = s.getReadEncoding();
             int sz = s.getReadEncapsSize();
             _rawBytes = new byte[sz];
             s.readBlob(_rawBytes);
-            s.endReadEncaps();
+
             calcHashValue();
         }
-        
+
         //
         // Marshal the endpoint
         //
         public override void streamWrite(BasicStream s)
         {
-            s.writeShort(_type);
             s.startWriteEncaps(_rawEncoding, Ice.FormatType.DefaultFormat);
             s.writeBlob(_rawBytes);
             s.endWriteEncaps();
         }
-        
+
         //
         // Convert the endpoint to its string form
         //
@@ -183,9 +68,9 @@ namespace IceInternal
 
         private sealed class InfoI : Ice.OpaqueEndpointInfo
         {
-            public InfoI(short type, Ice.EncodingVersion rawEncoding, byte[] rawBytes) : 
+            public InfoI(short type, Ice.EncodingVersion rawEncoding, byte[] rawBytes) :
                 base(-1, false, rawEncoding, rawBytes)
-            {                
+            {
                 _type = type;
             }
 
@@ -193,19 +78,19 @@ namespace IceInternal
             {
                 return _type;
             }
-                
+
             override public bool datagram()
             {
                 return false;
             }
-                
+
             override public bool secure()
             {
                 return false;
             }
 
             private readonly short _type;
-        };
+        }
 
         //
         // Return the endpoint information.
@@ -222,7 +107,7 @@ namespace IceInternal
         {
             return _type;
         }
-        
+
         //
         // Return the protocol name;
         //
@@ -239,7 +124,7 @@ namespace IceInternal
         {
             return -1;
         }
-        
+
         //
         // Return a new endpoint with a different timeout value, provided
         // that timeouts are supported by the endpoint. Otherwise the same
@@ -250,6 +135,11 @@ namespace IceInternal
             return this;
         }
 
+        public override string connectionId()
+        {
+            return "";
+        }
+
         //
         // Return a new endpoint with a different connection id.
         //
@@ -257,7 +147,7 @@ namespace IceInternal
         {
             return this;
         }
-        
+
         //
         // Return true if the endpoints support bzip2 compress, or false
         // otherwise.
@@ -266,7 +156,7 @@ namespace IceInternal
         {
             return false;
         }
-        
+
         //
         // Return a new endpoint with a different compression value,
         // provided that compression is supported by the
@@ -276,7 +166,7 @@ namespace IceInternal
         {
             return this;
         }
-        
+
         //
         // Return true if the endpoint is datagram-based.
         //
@@ -284,7 +174,7 @@ namespace IceInternal
         {
             return false;
         }
-        
+
         //
         // Return true if the endpoint is secure.
         //
@@ -294,6 +184,14 @@ namespace IceInternal
         }
 
         //
+        // Get the encoded endpoint.
+        //
+        public byte[] rawBytes()
+        {
+            return _rawBytes;
+        }
+
+        //
         // Return a server side transceiver for this endpoint, or null if a
         // transceiver can only be created by an acceptor. In case a
         // transceiver is created, this operation also returns a new
@@ -338,14 +236,13 @@ namespace IceInternal
         // host if listening on INADDR_ANY on server side or if no host
         // was specified on client side.
         //
-        public override List<EndpointI>
-        expand()
+        public override List<EndpointI> expand()
         {
             List<EndpointI> endps = new List<EndpointI>();
             endps.Add(this);
             return endps;
         }
-        
+
         //
         // Check whether the endpoint is equivalent to another one.
         //
@@ -358,7 +255,22 @@ namespace IceInternal
         {
             return _hashCode;
         }
-        
+
+        public override string options()
+        {
+            string s = "";
+            if(_type > -1)
+            {
+                s += " -t " + _type;
+            }
+            s += " -e " + Ice.Util.encodingVersionToString(_rawEncoding);
+            if(_rawBytes.Length > 0)
+            {
+                s += " -v " + IceUtilInternal.Base64.encode(_rawBytes);
+            }
+            return s;
+        }
+
         //
         // Compare endpoints for sorting purposes
         //
@@ -383,7 +295,7 @@ namespace IceInternal
             {
                 return 1;
             }
-            
+
             if(_rawEncoding.major < p._rawEncoding.major)
             {
                 return -1;
@@ -421,10 +333,96 @@ namespace IceInternal
                     return 1;
                 }
             }
-            
+
             return 0;
         }
-        
+
+        protected override bool checkOption(string option, string argument, string endpoint)
+        {
+            switch(option[1])
+            {
+            case 't':
+            {
+                if(_type > -1)
+                {
+                    throw new Ice.EndpointParseException("multiple -t options in endpoint " + endpoint);
+                }
+                if(argument == null)
+                {
+                    throw new Ice.EndpointParseException("no argument provided for -t option in endpoint " + endpoint);
+                }
+
+                int t;
+                try
+                {
+                    t = System.Int32.Parse(argument, CultureInfo.InvariantCulture);
+                }
+                catch(System.FormatException)
+                {
+                    throw new Ice.EndpointParseException("invalid type value `" + argument + "' in endpoint " +
+                                                         endpoint);
+                }
+
+                if(t < 0 || t > 65535)
+                {
+                    throw new Ice.EndpointParseException("type value `" + argument + "' out of range in endpoint " +
+                                                         endpoint);
+                }
+
+                _type = (short)t;
+                return true;
+            }
+
+            case 'v':
+            {
+                if(_rawBytes.Length > 0)
+                {
+                    throw new Ice.EndpointParseException("multiple -v options in endpoint " + endpoint);
+                }
+                if(argument == null)
+                {
+                    throw new Ice.EndpointParseException("no argument provided for -v option in endpoint " + endpoint);
+                }
+
+                for(int j = 0; j < argument.Length; ++j)
+                {
+                    if(!IceUtilInternal.Base64.isBase64(argument[j]))
+                    {
+                        throw new Ice.EndpointParseException("invalid base64 character `" + argument[j] +
+                                                             "' (ordinal " + ((int)argument[j]) +
+                                                             ") in endpoint " + endpoint);
+                    }
+                }
+                _rawBytes = IceUtilInternal.Base64.decode(argument);
+                return true;
+            }
+
+            case 'e':
+            {
+                if(argument == null)
+                {
+                    throw new Ice.EndpointParseException("no argument provided for -e option in endpoint " + endpoint);
+                }
+
+                try
+                {
+                    _rawEncoding = Ice.Util.stringToEncodingVersion(argument);
+                }
+                catch(Ice.VersionParseException e)
+                {
+                    throw new Ice.EndpointParseException("invalid encoding version `" + argument +
+                                                         "' in endpoint " + endpoint + ":\n" + e.str);
+                }
+                return true;
+            }
+
+            default:
+            {
+                return false;
+            }
+            }
+        }
+
         private void calcHashValue()
         {
             int h = 5381;
@@ -433,7 +431,7 @@ namespace IceInternal
             IceInternal.HashUtil.hashAdd(ref h, _rawBytes);
             _hashCode = h;
         }
-        
+
         private short _type;
         private Ice.EncodingVersion _rawEncoding;
         private byte[] _rawBytes;
diff --git a/cs/src/Ice/ProtocolInstance.cs b/cs/src/Ice/ProtocolInstance.cs
new file mode 100644
index 00000000000..cc66138ee54
--- /dev/null
+++ b/cs/src/Ice/ProtocolInstance.cs
@@ -0,0 +1,119 @@
+// **********************************************************************
+//
+// Copyright (c) 2003-2014 ZeroC, Inc. All rights reserved.
+//
+// This copy of Ice is licensed to you under the terms described in the
+// ICE_LICENSE file included in this distribution.
+//
+// **********************************************************************
+
+namespace IceInternal
+{
+
+    using System.Collections.Generic;
+
+    public class ProtocolInstance
+    {
+        public ProtocolInstance(Ice.Communicator communicator, short type, string protocol)
+        {
+            instance_ = Util.getInstance(communicator);
+            traceLevel_ = instance_.traceLevels().network;
+            traceCategory_ = instance_.traceLevels().networkCat;
+            logger_ = instance_.initializationData().logger;
+            properties_ = instance_.initializationData().properties;
+            type_ = type;
+            protocol_ = protocol;
+        }
+
+        public ProtocolInstance(Instance instance, short type, string protocol)
+        {
+            instance_ = instance;
+            traceLevel_ = instance_.traceLevels().network;
+            traceCategory_ = instance_.traceLevels().networkCat;
+            logger_ = instance_.initializationData().logger;
+            properties_ = instance_.initializationData().properties;
+            type_ = type;
+            protocol_ = protocol;
+        }
+
+        public int traceLevel()
+        {
+            return traceLevel_;
+        }
+
+        public string traceCategory()
+        {
+            return traceCategory_;
+        }
+
+        public Ice.Logger logger()
+        {
+            return logger_;
+        }
+
+        public string protocol()
+        {
+            return protocol_;
+        }
+
+        public short type()
+        {
+            return type_;
+        }
+
+        public Ice.Properties properties()
+        {
+            return properties_;
+        }
+
+        public bool preferIPv6()
+        {
+            return instance_.preferIPv6();
+        }
+
+        public int protocolSupport()
+        {
+            return instance_.protocolSupport();
+        }
+
+        public string defaultHost()
+        {
+            return instance_.defaultsAndOverrides().defaultHost;
+        }
+
+        public Ice.EncodingVersion defaultEncoding()
+        {
+            return instance_.defaultsAndOverrides().defaultEncoding;
+        }
+
+        public NetworkProxy networkProxy()
+        {
+            return instance_.networkProxy();
+        }
+
+        public int messageSizeMax()
+        {
+            return instance_.messageSizeMax();
+        }
+
+        public List<Connector> resolve(string host, int port, Ice.EndpointSelectionType type, IPEndpointI endpt)
+        {
+            return instance_.endpointHostResolver().resolve(host, port, type, endpt);
+        }
+
+        public void resolve(string host, int port, Ice.EndpointSelectionType type, IPEndpointI endpt,
+                            EndpointI_connectors callback)
+        {
+            instance_.endpointHostResolver().resolve(host, port, type, endpt, callback);
+        }
+
+        protected Instance instance_;
+        protected int traceLevel_;
+        protected string traceCategory_;
+        protected Ice.Logger logger_;
+        protected Ice.Properties properties_;
+        protected string protocol_;
+        protected short type_;
+    }
+
+}
diff --git a/cs/src/Ice/ProtocolPluginFacade.cs b/cs/src/Ice/ProtocolPluginFacade.cs
index 6a990b26fcd..9736239d66d 100644
--- a/cs/src/Ice/ProtocolPluginFacade.cs
+++ b/cs/src/Ice/ProtocolPluginFacade.cs
@@ -17,43 +17,6 @@ namespace IceInternal
         //
         Ice.Communicator getCommunicator();
 
-#if !SILVERLIGHT
-        //
-        // Get the endpoint host resolver.
-        //
-        IceInternal.EndpointHostResolver getEndpointHostResolver();
-#endif
-        //
-        // Get the protocol support.
-        //
-        int getProtocolSupport();
-
-        //
-        // Get the protocol support.
-        //
-        bool getPreferIPv6();
-
-        //
-        // Get the network proxy.
-        //
-        NetworkProxy getNetworkProxy();
-
-        //
-        // Get the default encoding to be used in endpoints.
-        //
-        Ice.EncodingVersion getDefaultEncoding();
-
-        //
-        // Get the default hostname to be used in endpoints.
-        //
-        string getDefaultHost();
-
-        //
-        // Get the network trace level and category name.
-        //
-        int getNetworkTraceLevel();
-        string getNetworkTraceCategory();
-
         //
         // Register an EndpointFactory.
         //
@@ -87,69 +50,6 @@ namespace IceInternal
             return _communicator;
         }
 
-#if !SILVERLIGHT
-        //
-        // Get the endpoint host resolver.
-        //
-        public IceInternal.EndpointHostResolver getEndpointHostResolver()
-        {
-            return _instance.endpointHostResolver();
-        }
-#endif
-
-        //
-        // Get the protocol support.
-        //
-        public int getProtocolSupport()
-        {
-            return _instance.protocolSupport();
-        }
-
-        //
-        // Get the protocol support.
-        //
-        public bool getPreferIPv6()
-        {
-            return _instance.preferIPv6();
-        }
-
-        //
-        // Get the network proxy.
-        //
-        public NetworkProxy getNetworkProxy()
-        {
-            return _instance.networkProxy();
-        }
-
-        //
-        // Get the default hostname to be used in endpoints.
-        //
-        public Ice.EncodingVersion getDefaultEncoding()
-        {
-            return _instance.defaultsAndOverrides().defaultEncoding;
-        }
-
-        //
-        // Get the default hostname to be used in endpoints.
-        //
-        public string getDefaultHost()
-        {
-            return _instance.defaultsAndOverrides().defaultHost;
-        }
-
-        //
-        // Get the network trace level and category name.
-        //
-        public int getNetworkTraceLevel()
-        {
-            return _instance.traceLevels().network;
-        }
-
-        public string getNetworkTraceCategory()
-        {
-            return _instance.traceLevels().networkCat;
-        }
-
         //
         // Register an EndpointFactory.
         //
diff --git a/cs/src/Ice/Reference.cs b/cs/src/Ice/Reference.cs
index 085c55ccabb..0f427cec53a 100644
--- a/cs/src/Ice/Reference.cs
+++ b/cs/src/Ice/Reference.cs
@@ -1017,9 +1017,10 @@ namespace IceInternal
             if(_endpoints.Length > 0)
             {
                 Debug.Assert(_adapterId.Length == 0);
-                for(int i = 0; i < _endpoints.Length; i++)
+                foreach(EndpointI endpoint in _endpoints)
                 {
-                    _endpoints[i].streamWrite(s);
+                    s.writeShort(endpoint.type());
+                    endpoint.streamWrite(s);
                 }
             }
             else
diff --git a/cs/src/Ice/TcpAcceptor.cs b/cs/src/Ice/TcpAcceptor.cs
index 633969bea86..833a2257d29 100644
--- a/cs/src/Ice/TcpAcceptor.cs
+++ b/cs/src/Ice/TcpAcceptor.cs
@@ -23,14 +23,13 @@ namespace IceInternal
     {
         public virtual void close()
         {
-            if(_traceLevels.network >= 1)
+            if(_instance.traceLevel() >= 1)
             {
-                string s = "stopping to accept tcp connections at " + ToString();
-                _logger.trace(_traceLevels.networkCat, s);
+                string s = "stopping to accept " + protocol() + " connections at " + ToString();
+                _instance.logger().trace(_instance.traceCategory(), s);
             }
 
             Debug.Assert(_acceptFd == null);
-
             _fd.Close();
             _fd = null;
         }
@@ -39,19 +38,19 @@ namespace IceInternal
         {
             Network.doListen(_fd, _backlog);
 
-            if(_traceLevels.network >= 1)
+            if(_instance.traceLevel() >= 1)
             {
-                StringBuilder s = new StringBuilder("listening for tcp connections at ");
+                StringBuilder s = new StringBuilder("listening for " + protocol() + " connections at ");
                 s.Append(ToString());
 
                 List<string> interfaces =
-                    Network.getHostsForEndpointExpand(_addr.Address.ToString(), instance_.protocolSupport(), true);
+                    Network.getHostsForEndpointExpand(_addr.Address.ToString(), _instance.protocolSupport(), true);
                 if(interfaces.Count != 0)
                 {
                     s.Append("\nlocal interfaces: ");
                     s.Append(String.Join(", ", interfaces.ToArray()));
                 }
-                _logger.trace(_traceLevels.networkCat, s.ToString());
+                _instance.logger().trace(_instance.traceCategory(), s.ToString());
             }
         }
 
@@ -99,19 +98,24 @@ namespace IceInternal
 
             Network.setBlock(_acceptFd, false);
 #  if !COMPACT
-            Network.setTcpBufSize(_acceptFd, instance_.initializationData().properties, _logger);
+            Network.setTcpBufSize(_acceptFd, _instance.properties(), _instance.logger());
 #  endif
 
-            if(_traceLevels.network >= 1)
+            if(_instance.traceLevel() >= 1)
             {
-                string s = "accepted tcp connection\n" + Network.fdToString(_acceptFd);
-                _logger.trace(_traceLevels.networkCat, s);
+                string s = "accepted " + protocol() + " connection\n" + Network.fdToString(_acceptFd);
+                _instance.logger().trace(_instance.traceCategory(), s);
             }
 
             Socket acceptFd = _acceptFd;
             _acceptFd = null;
             _acceptError = null;
-            return new TcpTransceiver(instance_, acceptFd, null, null, true);
+            return new TcpTransceiver(_instance, acceptFd, null, null, true);
+        }
+
+        public string protocol()
+        {
+            return _instance.protocol();
         }
 
         public override string ToString()
@@ -124,43 +128,42 @@ namespace IceInternal
             return _addr.Port;
         }
 
-        internal TcpAcceptor(Instance instance, string host, int port)
+        internal TcpAcceptor(ProtocolInstance instance, string host, int port)
         {
-            instance_ = instance;
-            _traceLevels = instance.traceLevels();
-            _logger = instance.initializationData().logger;
-            _backlog = instance.initializationData().properties.getPropertyAsIntWithDefault("Ice.TCP.Backlog", 511);
+            _instance = instance;
+            _backlog = instance.properties().getPropertyAsIntWithDefault("Ice.TCP.Backlog", 511);
 
             try
             {
-                int protocol = instance_.protocolSupport();
-                _addr = (IPEndPoint)Network.getAddressForServer(host, port, protocol, instance_.preferIPv6());
+                int protocol = _instance.protocolSupport();
+                _addr = (IPEndPoint)Network.getAddressForServer(host, port, protocol, _instance.preferIPv6());
                 _fd = Network.createServerSocket(false, _addr.AddressFamily, protocol);
                 Network.setBlock(_fd, false);
 #  if !COMPACT
-                Network.setTcpBufSize(_fd, instance_.initializationData().properties, _logger);
+                Network.setTcpBufSize(_fd, _instance.properties(), _instance.logger());
 #  endif
                 if(AssemblyUtil.platform_ != AssemblyUtil.Platform.Windows)
                 {
                     //
-                    // Enable SO_REUSEADDR on Unix platforms to allow
-                    // re-using the socket even if it's in the TIME_WAIT
-                    // state. On Windows, this doesn't appear to be
-                    // necessary and enabling SO_REUSEADDR would actually
-                    // not be a good thing since it allows a second
-                    // process to bind to an address even it's already
-                    // bound by another process.
+                    // Enable SO_REUSEADDR on Unix platforms to allow re-using the
+                    // socket even if it's in the TIME_WAIT state. On Windows,
+                    // this doesn't appear to be necessary and enabling
+                    // SO_REUSEADDR would actually not be a good thing since it
+                    // allows a second process to bind to an address even it's
+                    // already bound by another process.
                     //
-                    // TODO: using SO_EXCLUSIVEADDRUSE on Windows would
-                    // probably be better but it's only supported by recent
-                    // Windows versions (XP SP2, Windows Server 2003).
+                    // TODO: using SO_EXCLUSIVEADDRUSE on Windows would probably
+                    // be better but it's only supported by recent Windows
+                    // versions (XP SP2, Windows Server 2003).
                     //
                     Network.setReuseAddress(_fd, true);
                 }
-                if(_traceLevels.network >= 2)
+
+                if(_instance.traceLevel() >= 2)
                 {
-                    string s = "attempting to bind to tcp socket " + Network.addrToString(_addr);
-                    _logger.trace(_traceLevels.networkCat, s);
+                    string s = "attempting to bind to " + _instance.protocol() + " socket " +
+                        Network.addrToString(_addr);
+                    _instance.logger().trace(_instance.traceCategory(), s);
                 }
                 _addr = Network.doBind(_fd, _addr);
             }
@@ -171,9 +174,7 @@ namespace IceInternal
             }
         }
 
-        private Instance instance_;
-        private TraceLevels _traceLevels;
-        private Ice.Logger _logger;
+        private ProtocolInstance _instance;
         private Socket _fd;
         private Socket _acceptFd;
         private System.Exception _acceptError;
diff --git a/cs/src/Ice/TcpConnector.cs b/cs/src/Ice/TcpConnector.cs
index bf1e956e1d0..9fdcecff1ab 100644
--- a/cs/src/Ice/TcpConnector.cs
+++ b/cs/src/Ice/TcpConnector.cs
@@ -16,27 +16,25 @@ namespace IceInternal
 
     sealed class TcpConnector : Connector
     {
-        internal const short TYPE = 1;
-
         public Transceiver connect()
         {
-            if(_traceLevels.network >= 2)
+            if(_instance.traceLevel() >= 2)
             {
-                string s = "trying to establish tcp connection to " + ToString();
-                _logger.trace(_traceLevels.networkCat, s);
+                string s = "trying to establish " + _instance.protocol() + " connection to " + ToString();
+                _instance.logger().trace(_instance.traceCategory(), s);
             }
 
             try
             {
 #if SILVERLIGHT
                 Socket fd = Network.createSocket(false, _addr.AddressFamily == AddressFamily.InterNetworkV6 ?
-                                                        AddressFamily.InterNetworkV6 : AddressFamily.InterNetwork);
+                                                 AddressFamily.InterNetworkV6 : AddressFamily.InterNetwork);
 #else
                 Socket fd = Network.createSocket(false, _addr.AddressFamily);
                 Network.setBlock(fd, false);
 #endif
 #if !COMPACT
-                Network.setTcpBufSize(fd, _instance.initializationData().properties, _logger);
+                Network.setTcpBufSize(fd, _instance.properties(), _instance.logger());
 #endif
 
                 //
@@ -46,10 +44,11 @@ namespace IceInternal
             }
             catch(Ice.LocalException ex)
             {
-                if(_traceLevels.network >= 2)
+                if(_instance.traceLevel() >= 2)
                 {
-                    string s = "failed to establish tcp connection to " + ToString() + "\n" + ex;
-                    _logger.trace(_traceLevels.networkCat, s);
+                    string s = "failed to establish " + _instance.protocol() + " connection to " + ToString() + "\n" +
+                        ex;
+                    _instance.logger().trace(_instance.traceCategory(), s);
                 }
                 throw;
             }
@@ -57,17 +56,16 @@ namespace IceInternal
 
         public short type()
         {
-            return Ice.UDPEndpointType.value;
+            return _instance.type();
         }
 
         //
         // Only for use by TcpEndpoint
         //
-        internal TcpConnector(Instance instance, EndPoint addr, NetworkProxy proxy, int timeout, string connectionId)
+        internal TcpConnector(ProtocolInstance instance, EndPoint addr, NetworkProxy proxy, int timeout,
+                              string connectionId)
         {
             _instance = instance;
-            _traceLevels = instance.traceLevels();
-            _logger = instance.initializationData().logger;
             _addr = addr;
             _proxy = proxy;
             _timeout = timeout;
@@ -115,9 +113,7 @@ namespace IceInternal
             return _hashCode;
         }
 
-        private Instance _instance;
-        private TraceLevels _traceLevels;
-        private Ice.Logger _logger;
+        private ProtocolInstance _instance;
         private EndPoint _addr;
         private NetworkProxy _proxy;
         private int _timeout;
diff --git a/cs/src/Ice/TcpEndpointI.cs b/cs/src/Ice/TcpEndpointI.cs
index c09f2756f89..cb1f556d981 100644
--- a/cs/src/Ice/TcpEndpointI.cs
+++ b/cs/src/Ice/TcpEndpointI.cs
@@ -15,296 +15,66 @@ namespace IceInternal
     using System;
     using System.Globalization;
 
-    sealed class TcpEndpointI : EndpointI
+    sealed class TcpEndpointI : IPEndpointI
     {
-        public TcpEndpointI(Instance instance, string ho, int po, int ti, string conId, bool co) : base(conId)
+        public TcpEndpointI(ProtocolInstance instance, string ho, int po, int ti, string conId, bool co) :
+            base(instance, ho, po, conId)
         {
-            _instance = instance;
-            _host = ho;
-            _port = po;
             _timeout = ti;
             _compress = co;
-            calcHashValue();
         }
 
-        public TcpEndpointI(Instance instance, string str, bool oaEndpoint) : base("")
+        public TcpEndpointI(ProtocolInstance instance) :
+            base(instance)
         {
-            _instance = instance;
-            _host = null;
-            _port = 0;
             _timeout = -1;
             _compress = false;
-
-            char[] separators = { ' ', '\t', '\n', '\r' };
-            string[] arr = str.Split(separators);
-
-            int i = 0;
-            while(i < arr.Length)
-            {
-                if(arr[i].Length == 0)
-                {
-                    i++;
-                    continue;
-                }
-
-                string option = arr[i++];
-                if(option.Length != 2 || option[0] != '-')
-                {
-                    Ice.EndpointParseException e = new Ice.EndpointParseException();
-                    e.str = "expected an endpoint option but found `" + option + "' in endpoint `tcp " + str + "'";
-                    throw e;
-                }
-
-                string argument = null;
-                if(i < arr.Length && arr[i].Length > 0 && arr[i][0] != '-')
-                {
-                    argument = arr[i++];
-                    if(argument[0] == '\"' && argument[argument.Length - 1] == '\"')
-                    {
-                        argument = argument.Substring(1, argument.Length - 2);
-                    }
-                }
-
-                switch(option[1])
-                {
-                    case 'h':
-                    {
-                        if(argument == null)
-                        {
-                            Ice.EndpointParseException e = new Ice.EndpointParseException();
-                            e.str = "no argument provided for -h option in endpoint `tcp " + str + "'";
-                            throw e;
-                        }
-
-                        _host = argument;
-                        break;
-                    }
-
-                    case 'p':
-                    {
-                        if(argument == null)
-                        {
-                            Ice.EndpointParseException e = new Ice.EndpointParseException();
-                            e.str = "no argument provided for -p option in endpoint `tcp " + str + "'";
-                            throw e;
-                        }
-
-                        try
-                        {
-                            _port = System.Int32.Parse(argument, CultureInfo.InvariantCulture);
-                        }
-                        catch(System.FormatException ex)
-                        {
-                            Ice.EndpointParseException e = new Ice.EndpointParseException(ex);
-                            e.str = "invalid port value `" + argument + "' in endpoint `tcp " + str + "'";
-                            throw e;
-                        }
-
-                        if(_port < 0 || _port > 65535)
-                        {
-                            Ice.EndpointParseException e = new Ice.EndpointParseException();
-                            e.str = "port value `" + argument + "' out of range in endpoint `tcp " + str + "'";
-                            throw e;
-                        }
-
-                        break;
-                    }
-
-                    case 't':
-                    {
-                        if(argument == null)
-                        {
-                            Ice.EndpointParseException e = new Ice.EndpointParseException();
-                            e.str = "no argument provided for -t option in endpoint `tcp " + str + "'";
-                            throw e;
-                        }
-
-                        try
-                        {
-                            _timeout = System.Int32.Parse(argument, CultureInfo.InvariantCulture);
-                        }
-                        catch(System.FormatException ex)
-                        {
-                            Ice.EndpointParseException e = new Ice.EndpointParseException(ex);
-                            e.str = "invalid timeout value `" + argument + "' in endpoint `tcp " + str + "'";
-                            throw e;
-                        }
-
-                        break;
-                    }
-
-                    case 'z':
-                    {
-                        if(argument != null)
-                        {
-                            Ice.EndpointParseException e = new Ice.EndpointParseException();
-                            e.str = "unexpected argument `" + argument + "' provided for -z option in `tcp " + str +
-                                    "'";
-                            throw e;
-                        }
-
-                        _compress = true;
-                        break;
-                    }
-
-                    default:
-                    {
-                        throw new Ice.EndpointParseException("unknown option `" + option + "' in endpoint `tcp " + str + "'");
-                    }
-                }
-            }
-
-            if(_host == null)
-            {
-                _host = _instance.defaultsAndOverrides().defaultHost;
-            }
-            else if(_host.Equals("*"))
-            {
-                if(oaEndpoint)
-                {
-                    _host = null;
-                }
-                else
-                {
-                    throw new Ice.EndpointParseException("`-h *' not valid for proxy endpoint `tcp " + str + "'");
-                }
-            }
-
-            if(_host == null)
-            {
-                _host = "";
-            }
-
-            calcHashValue();
         }
 
-        public TcpEndpointI(BasicStream s)
+        public TcpEndpointI(ProtocolInstance instance, BasicStream s) :
+            base(instance, s)
         {
-            _instance = s.instance();
-            s.startReadEncaps();
-            _host = s.readString();
-            _port = s.readInt();
             _timeout = s.readInt();
             _compress = s.readBool();
-            s.endReadEncaps();
-            calcHashValue();
-        }
-
-        //
-        // Marshal the endpoint
-        //
-        public override void streamWrite(BasicStream s)
-        {
-            s.writeShort(Ice.TCPEndpointType.value);
-            s.startWriteEncaps();
-            s.writeString(_host);
-            s.writeInt(_port);
-            s.writeInt(_timeout);
-            s.writeBool(_compress);
-            s.endWriteEncaps();
         }
 
-        //
-        // Convert the endpoint to its string form
-        //
-        public override string ice_toString_()
+        private sealed class InfoI : Ice.TCPEndpointInfo
         {
-            //
-            // WARNING: Certain features, such as proxy validation in Glacier2,
-            // depend on the format of proxy strings. Changes to toString() and
-            // methods called to generate parts of the reference string could break
-            // these features. Please review for all features that depend on the
-            // format of proxyToString() before changing this and related code.
-            //
-            string s = "tcp";
-
-            if(_host != null && _host.Length != 0)
+            public InfoI(IPEndpointI e)
             {
-                s += " -h ";
-                bool addQuote = _host.IndexOf(':') != -1;
-                if(addQuote)
-                {
-                    s += "\"";
-                }
-                s += _host;
-                if(addQuote)
-                {
-                    s += "\"";
-                }
+                _endpoint = e;
             }
 
-            s += " -p " + _port;
-            if(_timeout != -1)
-            {
-                s += " -t " + _timeout;
-            }
-            if(_compress)
+            public override short type()
             {
-                s += " -z";
+                return _endpoint.type();
             }
-            return s;
-        }
 
-        private sealed class InfoI : Ice.TCPEndpointInfo
-        {
-            public InfoI(int to, bool comp, string host, int port) : base(to, comp, host, port)
+            public override bool datagram()
             {
+                return _endpoint.datagram();
             }
 
-            override public short type()
-            {
-                return Ice.TCPEndpointType.value;
-            }
-            
-            override public bool datagram()
-            {
-                return false;
-            }
-                
-            override public bool secure()
+            public override bool secure()
             {
-                return false;
+                return _endpoint.secure();
             }
-        };
 
-        //
-        // Return the endpoint information.
-        //
-        public override Ice.EndpointInfo getInfo()
-        {
-            return new InfoI(_timeout, _compress, _host, _port);
-        }
-
-        //
-        // Return the endpoint type
-        //
-        public override short type()
-        {
-            return Ice.TCPEndpointType.value;
+            private IPEndpointI _endpoint;
         }
 
-        //
-        // Return the protocol name;
-        //
-        public override string protocol()
+        public override Ice.EndpointInfo getInfo()
         {
-            return "tcp";
+            InfoI info = new InfoI(this);
+            fillEndpointInfo(info);
+            return info;
         }
 
-        //
-        // Return the timeout for the endpoint in milliseconds. 0 means
-        // non-blocking, -1 means no timeout.
-        //
         public override int timeout()
         {
             return _timeout;
         }
 
-        //
-        // Return a new endpoint with a different timeout value, provided
-        // that timeouts are supported by the endpoint. Otherwise the same
-        // endpoint is returned.
-        //
         public override EndpointI timeout(int timeout)
         {
             if(timeout == _timeout)
@@ -313,39 +83,15 @@ namespace IceInternal
             }
             else
             {
-                return new TcpEndpointI(_instance, _host, _port, timeout, connectionId_, _compress);
+                return new TcpEndpointI(instance_, host_, port_, timeout, connectionId_, _compress);
             }
         }
 
-        //
-        // Return a new endpoint with a different connection id.
-        //
-        public override EndpointI connectionId(string connectionId)
-        {
-            if(connectionId == connectionId_)
-            {
-                return this;
-            }
-            else
-            {
-                return new TcpEndpointI(_instance, _host, _port, _timeout, connectionId, _compress);
-            }
-        }
-
-        //
-        // Return true if the endpoints support bzip2 compress, or false
-        // otherwise.
-        //
         public override bool compress()
         {
             return _compress;
         }
 
-        //
-        // Return a new endpoint with a different compression value,
-        // provided that compression is supported by the
-        // endpoint. Otherwise the same endpoint is returned.
-        //
         public override EndpointI compress(bool compress)
         {
             if(compress == _compress)
@@ -354,141 +100,61 @@ namespace IceInternal
             }
             else
             {
-                return new TcpEndpointI(_instance, _host, _port, _timeout, connectionId_, compress);
+                return new TcpEndpointI(instance_, host_, port_, _timeout, connectionId_, compress);
             }
         }
 
-        //
-        // Return true if the endpoint is datagram-based.
-        //
         public override bool datagram()
         {
             return false;
         }
 
-        //
-        // Return true if the endpoint is secure.
-        //
         public override bool secure()
         {
             return false;
         }
 
-        //
-        // Return a server side transceiver for this endpoint, or null if a
-        // transceiver can only be created by an acceptor. In case a
-        // transceiver is created, this operation also returns a new
-        // "effective" endpoint, which might differ from this endpoint,
-        // for example, if a dynamic port number is assigned.
-        //
         public override Transceiver transceiver(ref EndpointI endpoint)
         {
             endpoint = this;
             return null;
         }
 
-        //
-        // Return connectors for this endpoint, or empty list if no connector
-        // is available.
-        //
-        public override List<Connector> connectors(Ice.EndpointSelectionType selType)
-        {
-#if SILVERLIGHT
-            return connectors(Network.getAddresses(_host, 
-                                                   _port,
-                                                   _instance.protocolSupport(), 
-                                                   selType, 
-                                                   _instance.preferIPv6(), 
-                                                   false),
-                              _instance.networkProxy());
-#else
-            return _instance.endpointHostResolver().resolve(_host, _port, selType, this);
-#endif
-        }
-
-
-        public override void connectors_async(Ice.EndpointSelectionType selType, EndpointI_connectors callback)
-        {
-#if SILVERLIGHT
-            callback.connectors(connectors(selType));
-#else
-            _instance.endpointHostResolver().resolve(_host, _port, selType, this, callback);
-#endif
-        }
-
-
-        //
-        // Return an acceptor for this endpoint, or null if no acceptors
-        // is available. In case an acceptor is created, this operation
-        // also returns a new "effective" endpoint, which might differ
-        // from this endpoint, for example, if a dynamic port number is
-        // assigned.
-        //
         public override Acceptor acceptor(ref EndpointI endpoint, string adapterName)
         {
 #if SILVERLIGHT
             throw new Ice.FeatureNotSupportedException("server endpoint not supported for `" + ToString() + "'");
 #else
-            TcpAcceptor p = new TcpAcceptor(_instance, _host, _port);
-            endpoint = new TcpEndpointI(_instance, _host, p.effectivePort(), _timeout, connectionId_, _compress);
+            TcpAcceptor p = new TcpAcceptor(instance_, host_, port_);
+            endpoint = createEndpoint(host_, p.effectivePort(), connectionId_);
             return p;
 #endif
         }
 
-        //
-        // Expand endpoint out in to separate endpoints for each local
-        // host if listening on INADDR_ANY.
-        //
-        public override List<EndpointI> expand()
+        public override string options()
         {
-            List<EndpointI> endps = new List<EndpointI>();
-            List<string> hosts = Network.getHostsForEndpointExpand(_host, _instance.protocolSupport(), false);
-            if(hosts == null || hosts.Count == 0)
-            {
-                endps.Add(this);
-            }
-            else
-            {
-                foreach(string h in hosts)
-                {
-                    endps.Add(new TcpEndpointI(_instance, h, _port, _timeout, connectionId_, _compress));
-                }
-            }
-            return endps;
-        }
+            //
+            // WARNING: Certain features, such as proxy validation in Glacier2,
+            // depend on the format of proxy strings. Changes to toString() and
+            // methods called to generate parts of the reference string could break
+            // these features. Please review for all features that depend on the
+            // format of proxyToString() before changing this and related code.
+            //
+            string s = base.options();
 
-        //
-        // Check whether the endpoint is equivalent to another one.
-        //
-        public override bool equivalent(EndpointI endpoint)
-        {
-            if(!(endpoint is TcpEndpointI))
+            if(_timeout != -1)
             {
-                return false;
+                s += " -t " + _timeout;
             }
 
-            TcpEndpointI tcpEndpointI = (TcpEndpointI)endpoint;
-            return tcpEndpointI._host.Equals(_host) && tcpEndpointI._port == _port;
-        }
-
-        public override List<Connector> connectors(List<EndPoint> addresses, NetworkProxy networkProxy)
-        {
-            List<Connector> connectors = new List<Connector>();
-            foreach(EndPoint addr in addresses)
+            if(_compress)
             {
-                connectors.Add(new TcpConnector(_instance, addr, networkProxy, _timeout, connectionId_));
+                s += " -z";
             }
-            return connectors;
-        }
 
-        public override int GetHashCode()
-        {
-            return _hashCode;
+            return s;
         }
 
-        //
-        // Compare endpoints for sorting purposes
-        //
         public override int CompareTo(EndpointI obj)
         {
             if(!(obj is TcpEndpointI))
@@ -501,23 +167,6 @@ namespace IceInternal
             {
                 return 0;
             }
-            else
-            {
-                int r = base.CompareTo(p);
-                if(r != 0)
-                {
-                    return r;
-                }
-            }
-
-            if(_port < p._port)
-            {
-                return -1;
-            }
-            else if(p._port < _port)
-            {
-                return 1;
-            }
 
             if(_timeout < p._timeout)
             {
@@ -537,54 +186,126 @@ namespace IceInternal
                 return 1;
             }
 
-            return string.Compare(_host, p._host, StringComparison.Ordinal);
+            return base.CompareTo(p);
+        }
+
+        protected override void streamWriteImpl(BasicStream s)
+        {
+            base.streamWriteImpl(s);
+            s.writeInt(_timeout);
+            s.writeBool(_compress);
         }
 
-        private void calcHashValue()
+        protected override void hashInit(ref int h)
         {
-            int h = 5381;
-            IceInternal.HashUtil.hashAdd(ref h, Ice.TCPEndpointType.value);
-            IceInternal.HashUtil.hashAdd(ref h, _host);
-            IceInternal.HashUtil.hashAdd(ref h, _port);
+            base.hashInit(ref h);
             IceInternal.HashUtil.hashAdd(ref h, _timeout);
-            IceInternal.HashUtil.hashAdd(ref h, connectionId_);
             IceInternal.HashUtil.hashAdd(ref h, _compress);
-            _hashCode = h;
         }
 
-        private Instance _instance;
-        private string _host;
-        private int _port;
+        protected override void fillEndpointInfo(Ice.IPEndpointInfo info)
+        {
+            base.fillEndpointInfo(info);
+            if(info is Ice.TCPEndpointInfo)
+            {
+                Ice.TCPEndpointInfo tcpInfo = (Ice.TCPEndpointInfo)info;
+                tcpInfo.timeout = _timeout;
+                tcpInfo.compress = _compress;
+            }
+        }
+
+        protected override bool checkOption(string option, string argument, string endpoint)
+        {
+            if(base.checkOption(option, argument, endpoint))
+            {
+                return true;
+            }
+
+            switch(option[1])
+            {
+                case 't':
+                {
+                    if(argument == null)
+                    {
+                        throw new Ice.EndpointParseException("no argument provided for -t option in endpoint " +
+                                                             endpoint);
+                    }
+
+                    try
+                    {
+                        _timeout = System.Int32.Parse(argument, CultureInfo.InvariantCulture);
+                    }
+                    catch(System.FormatException ex)
+                    {
+                        Ice.EndpointParseException e = new Ice.EndpointParseException(ex);
+                        e.str = "invalid timeout value `" + argument + "' in endpoint " + endpoint;
+                        throw e;
+                    }
+
+                    return true;
+                }
+
+                case 'z':
+                {
+                    if(argument != null)
+                    {
+                        throw new Ice.EndpointParseException("unexpected argument `" + argument +
+                                                             "' provided for -z option in " + endpoint);
+                    }
+
+                    _compress = true;
+
+                    return true;
+                }
+
+                default:
+                {
+                    return false;
+                }
+            }
+        }
+
+        protected override Connector createConnector(EndPoint addr, NetworkProxy proxy)
+        {
+            return new TcpConnector(instance_, addr, proxy, _timeout, connectionId_);
+        }
+
+        protected override IPEndpointI createEndpoint(string host, int port, string connectionId)
+        {
+            return new TcpEndpointI(instance_, host, port, _timeout, connectionId, _compress);
+        }
+
         private int _timeout;
         private bool _compress;
-        private int _hashCode;
     }
 
     sealed class TcpEndpointFactory : EndpointFactory
     {
-        internal TcpEndpointFactory(Instance instance)
+        internal TcpEndpointFactory(ProtocolInstance instance)
         {
             _instance = instance;
         }
 
         public short type()
         {
-            return Ice.TCPEndpointType.value;
+            return _instance.type();
         }
 
         public string protocol()
         {
-            return "tcp";
+            return _instance.protocol();
         }
 
-        public EndpointI create(string str, bool oaEndpoint)
+        public EndpointI create(List<string> args, bool oaEndpoint)
         {
-            return new TcpEndpointI(_instance, str, oaEndpoint);
+            IPEndpointI endpt = new TcpEndpointI(_instance);
+            endpt.initWithOptions(args, oaEndpoint);
+            return endpt;
         }
 
         public EndpointI read(BasicStream s)
         {
-            return new TcpEndpointI(s);
+            return new TcpEndpointI(_instance, s);
         }
 
         public void destroy()
@@ -592,7 +313,12 @@ namespace IceInternal
             _instance = null;
         }
 
-        private Instance _instance;
+        public EndpointFactory clone(ProtocolInstance instance)
+        {
+            return new TcpEndpointFactory(instance);
+        }
+
+        private ProtocolInstance _instance;
     }
 
 }
diff --git a/cs/src/Ice/TcpTransceiver.cs b/cs/src/Ice/TcpTransceiver.cs
index 27a214c4ccd..1e9ead6b36d 100644
--- a/cs/src/Ice/TcpTransceiver.cs
+++ b/cs/src/Ice/TcpTransceiver.cs
@@ -25,7 +25,7 @@ namespace IceInternal
 
     sealed class TcpTransceiver : Transceiver
     {
-        public int initialize()
+        public int initialize(Buffer readBuffer, Buffer writeBuffer, ref bool hasMoreData)
         {
             try
             {
@@ -54,10 +54,11 @@ namespace IceInternal
                     _writeResult = null;
 #endif
                     _desc = Network.fdToString(_fd, _proxy, _addr);
+
                     if(_proxy != null)
                     {
                         _state = StateProxyConnectRequest; // Send proxy connect request
-                        return SocketOperation.Write; 
+                        return SocketOperation.Write;
                     }
 
                     _state = StateConnected;
@@ -74,37 +75,44 @@ namespace IceInternal
             }
             catch(Ice.LocalException ex)
             {
-                if(_traceLevels.network >= 2)
+                if(_instance.traceLevel() >= 2)
                 {
                     System.Text.StringBuilder s = new System.Text.StringBuilder();
-                    s.Append("failed to establish tcp connection\n");
+                    s.Append("failed to establish " + protocol() + " connection\n");
                     s.Append(Network.fdToString(_fd, _proxy, _addr));
                     s.Append("\n");
                     s.Append(ex.ToString());
-                    _logger.trace(_traceLevels.networkCat, s.ToString());
+                    _instance.logger().trace(_instance.traceCategory(), s.ToString());
                 }
                 throw;
             }
 
             Debug.Assert(_state == StateConnected);
-            if(_traceLevels.network >= 1)
+            if(_instance.traceLevel() >= 1)
             {
-                string s = "tcp connection established\n" + _desc;
-                _logger.trace(_traceLevels.networkCat, s);
+                string s = protocol() + " connection established\n" + _desc;
+                _instance.logger().trace(_instance.traceCategory(), s);
             }
             return SocketOperation.None;
         }
 
+        public int closing(bool initiator, Ice.LocalException ex)
+        {
+            // If we are initiating the connection closure, wait for the peer
+            // to close the TCP/IP connection. Otherwise, close immediately.
+            return initiator ? SocketOperation.Read : SocketOperation.None;
+        }
+
         public void close()
         {
             //
             // If the transceiver is not connected, its description is simply "not connected",
             // which isn't very helpful.
             //
-            if(_state == StateConnected && _traceLevels.network >= 1)
+            if(_state == StateConnected && _instance.traceLevel() >= 1)
             {
-                string s = "closing tcp connection\n" + ToString();
-                _logger.trace(_traceLevels.networkCat, s);
+                string s = "closing " + protocol() + " connection\n" + ToString();
+                _instance.logger().trace(_instance.traceCategory(), s);
             }
 
             Debug.Assert(_fd != null);
@@ -122,17 +130,22 @@ namespace IceInternal
             }
         }
 
-        public bool write(Buffer buf)
+        public int write(Buffer buf)
         {
 #if COMPACT || SILVERLIGHT
             //
             // Silverlight and the Compact .NET Frameworks don't support the use of synchronous socket
-            // operations on a non-blocking socket. Returning false here forces the caller to schedule
-            // an asynchronous operation.
+            // operations on a non-blocking socket. Returning SocketOperation.Write here forces the caller
+            // to schedule an asynchronous operation.
             //
-            return false;
+            return SocketOperation.Write;
 #else
             int packetSize = buf.b.remaining();
+            if(packetSize == 0)
+            {
+                return SocketOperation.None;
+            }
+
             if(AssemblyUtil.platform_ == AssemblyUtil.Platform.Windows)
             {
                 //
@@ -161,17 +174,17 @@ namespace IceInternal
                     {
                         if(Network.wouldBlock(e))
                         {
-                            return false;
+                            return SocketOperation.Write;
                         }
                         throw;
                     }
 
                     Debug.Assert(ret > 0);
 
-                    if(_traceLevels.network >= 3)
+                    if(_instance.traceLevel() >= 3)
                     {
-                        string s = "sent " + ret + " of " + packetSize + " bytes via tcp\n" + ToString();
-                        _logger.trace(_traceLevels.networkCat, s);
+                        string s = "sent " + ret + " of " + packetSize + " bytes via " + protocol() + "\n" + ToString();
+                        _instance.logger().trace(_instance.traceCategory(), s);
                     }
                     buf.b.position(buf.b.position() + ret);
                     if(packetSize > buf.b.remaining())
@@ -190,21 +203,25 @@ namespace IceInternal
                 }
             }
 
-            return true; // No more data to send.
+            return SocketOperation.None; // No more data to send.
 #endif
         }
 
-        public bool read(Buffer buf)
+        public int read(Buffer buf, ref bool hasMoreData)
         {
 #if COMPACT || SILVERLIGHT
             //
             // Silverlight and the Compact .NET Framework don't support the use of synchronous socket
             // operations on a non-blocking socket.
             //
-            return false;
+            return SocketOperation.Read;
 #else
             int remaining = buf.b.remaining();
             int position = buf.b.position();
+            if(remaining == 0)
+            {
+                return SocketOperation.None;
+            }
 
             while(buf.b.hasRemaining())
             {
@@ -229,19 +246,20 @@ namespace IceInternal
                     {
                         if(Network.wouldBlock(e))
                         {
-                            return false;
+                            return SocketOperation.Read;
                         }
                         throw;
                     }
 
                     Debug.Assert(ret > 0);
 
-                    if(_traceLevels.network >= 3)
+                    if(_instance.traceLevel() >= 3)
                     {
-                        string s = "received " + ret + " of " + remaining + " bytes via tcp\n" + ToString();
-                        _logger.trace(_traceLevels.networkCat, s);
+                        string s = "received " + ret + " of " + remaining + " bytes via " + protocol() + "\n" +
+                            ToString();
+                        _instance.logger().trace(_instance.traceCategory(), s);
                     }
-                    
+
                     remaining -= ret;
                     buf.b.position(position += ret);
                 }
@@ -271,7 +289,7 @@ namespace IceInternal
                 }
             }
 
-            return true;
+            return SocketOperation.None;
 #endif
         }
 
@@ -354,15 +372,15 @@ namespace IceInternal
 
                 Debug.Assert(ret > 0);
 
-                if(_traceLevels.network >= 3)
+                if(_instance.traceLevel() >= 3)
                 {
                     int packetSize = buf.b.remaining();
                     if(_maxReceivePacketSize > 0 && packetSize > _maxReceivePacketSize)
                     {
                         packetSize = _maxReceivePacketSize;
                     }
-                    string s = "received " + ret + " of " + packetSize + " bytes via tcp\n" + ToString();
-                    _logger.trace(_traceLevels.networkCat, s);
+                    string s = "received " + ret + " of " + packetSize + " bytes via " + protocol() + "\n" + ToString();
+                    _instance.logger().trace(_instance.traceCategory(), s);
                 }
 
                 buf.b.position(buf.b.position() + ret);
@@ -442,7 +460,7 @@ namespace IceInternal
                 _writeEventArgs.SetBuffer(buf.b.rawBytes(), buf.b.position(), packetSize);
                 bool completedSynchronously = !_fd.SendAsync(_writeEventArgs);
 #else
-                _writeResult = _fd.BeginSend(buf.b.rawBytes(), buf.b.position(), packetSize, SocketFlags.None, 
+                _writeResult = _fd.BeginSend(buf.b.rawBytes(), buf.b.position(), packetSize, SocketFlags.None,
                                              writeCompleted, state);
                 bool completedSynchronously = _writeResult.CompletedSynchronously;
 #endif
@@ -489,8 +507,8 @@ namespace IceInternal
             if(_state < StateConnected && _state != StateProxyConnectRequest)
             {
                 return;
-            } 
-            
+            }
+
             try
             {
 #if ICE_SOCKET_ASYNC_API
@@ -509,15 +527,15 @@ namespace IceInternal
                 }
                 Debug.Assert(ret > 0);
 
-                if(_traceLevels.network >= 3)
+                if(_instance.traceLevel() >= 3)
                 {
                     int packetSize = buf.b.remaining();
                     if(_maxSendPacketSize > 0 && packetSize > _maxSendPacketSize)
                     {
                         packetSize = _maxSendPacketSize;
                     }
-                    string s = "sent " + ret + " of " + packetSize + " bytes via tcp\n" + ToString();
-                    _logger.trace(_traceLevels.networkCat, s);
+                    string s = "sent " + ret + " of " + packetSize + " bytes via " + protocol() + "\n" + ToString();
+                    _instance.logger().trace(_instance.traceCategory(), s);
                 }
 
                 buf.b.position(buf.b.position() + ret);
@@ -542,13 +560,12 @@ namespace IceInternal
             }
         }
 
-        public string type()
+        public string protocol()
         {
-            return "tcp";
+            return _instance.protocol();
         }
 
-        public Ice.ConnectionInfo
-        getInfo()
+        public Ice.ConnectionInfo getInfo()
         {
             Ice.TCPConnectionInfo info = new Ice.TCPConnectionInfo();
             if(_fd != null)
@@ -579,17 +596,16 @@ namespace IceInternal
         //
         // Only for use by TcpConnector, TcpAcceptor
         //
-        internal TcpTransceiver(Instance instance, Socket fd, EndPoint addr, NetworkProxy proxy, bool connected)
+        internal TcpTransceiver(ProtocolInstance instance, Socket fd, EndPoint addr, NetworkProxy proxy, bool connected)
         {
+            _instance = instance;
             _fd = fd;
             _addr = addr;
             _proxy = proxy;
-            
-            _traceLevels = instance.traceLevels();
-            _logger = instance.initializationData().logger;
+
             _state = connected ? StateConnected : StateNeedConnect;
             _desc = connected ? Network.fdToString(_fd, _proxy, _addr) : "<not connected>";
-            
+
 #if ICE_SOCKET_ASYNC_API
             _readEventArgs = new SocketAsyncEventArgs();
             _readEventArgs.Completed += new EventHandler<SocketAsyncEventArgs>(ioCompleted);
@@ -597,7 +613,7 @@ namespace IceInternal
             _writeEventArgs = new SocketAsyncEventArgs();
             _writeEventArgs.Completed += new EventHandler<SocketAsyncEventArgs>(ioCompleted);
 #if SILVERLIGHT
-            String policy = instance.initializationData().properties.getProperty("Ice.ClientAccessPolicyProtocol");
+            String policy = instance.properties().getProperty("Ice.ClientAccessPolicyProtocol");
             if(policy.Equals("Http"))
             {
                 _readEventArgs.SocketClientAccessPolicyProtocol = SocketClientAccessPolicyProtocol.Http;
@@ -605,7 +621,7 @@ namespace IceInternal
             }
             else if(!String.IsNullOrEmpty(policy))
             {
-                _logger.warning("Ignoring invalid Ice.ClientAccessPolicyProtocol value `" + policy + "'");
+                _instance.logger().warning("Ignoring invalid Ice.ClientAccessPolicyProtocol value `" + policy + "'");
             }
 #endif
 #endif
@@ -657,11 +673,10 @@ namespace IceInternal
         }
 #endif
 
+        private ProtocolInstance _instance;
         private Socket _fd;
         private EndPoint _addr;
         private NetworkProxy _proxy;
-        private TraceLevels _traceLevels;
-        private Ice.Logger _logger;
         private string _desc;
         private int _state;
         private int _maxSendPacketSize;
@@ -681,7 +696,7 @@ namespace IceInternal
         private const int StateNeedConnect = 0;
         private const int StateConnectPending = 1;
         private const int StateProxyConnectRequest = 2;
-        private const int StateProxyConnectRequestPending = 3; 
+        private const int StateProxyConnectRequestPending = 3;
         private const int StateConnected = 4;
     }
 }
diff --git a/cs/src/Ice/ThreadPool.cs b/cs/src/Ice/ThreadPool.cs
index 22852069b3e..84d1861e3cb 100644
--- a/cs/src/Ice/ThreadPool.cs
+++ b/cs/src/Ice/ThreadPool.cs
@@ -33,21 +33,21 @@ namespace IceInternal
             _finishWithIO = current.startMessage();
             return _finishWithIO;
         }
-        
+
         public void finishIOScope(ref ThreadPoolCurrent current)
         {
             if(_finishWithIO)
             {
-                // This must be called with the handler locked. 
+                // This must be called with the handler locked.
                 current.finishMessage(true);
             }
         }
-        
+
         public void completed(ref ThreadPoolCurrent current)
         {
             //
             // Call finishMessage once IO is completed only if serialization is not enabled.
-            // Otherwise, finishMessage will be called when the event handler is done with 
+            // Otherwise, finishMessage will be called when the event handler is done with
             // the message (it will be called from destroy below).
             //
             Debug.Assert(_finishWithIO);
@@ -57,14 +57,14 @@ namespace IceInternal
                 _finish = true;
             }
         }
-        
+
         public void destroy(ref ThreadPoolCurrent current)
         {
             if(_finish)
             {
                 //
                 // A ThreadPoolMessage instance must be created outside the synchronization
-                // of the event handler. We need to lock the event handler here to call 
+                // of the event handler. We need to lock the event handler here to call
                 // finishMessage.
                 //
                 _mutex.Lock();
@@ -79,7 +79,7 @@ namespace IceInternal
                 }
             }
         }
-        
+
         private IceUtilInternal.Monitor _mutex;
         private bool _finish;
         private bool _finishWithIO;
@@ -121,17 +121,17 @@ namespace IceInternal
     {
         public ThreadPool(Instance instance, string prefix, int timeout)
         {
+            Ice.Properties properties = instance.initializationData().properties;
+
             _instance = instance;
             _dispatcher = instance.initializationData().dispatcher;
             _destroyed = false;
             _prefix = prefix;
             _threadIndex = 0;
             _inUse = 0;
-            _serialize = _instance.initializationData().properties.getPropertyAsInt(_prefix + ".Serialize") > 0;
+            _serialize = properties.getPropertyAsInt(_prefix + ".Serialize") > 0;
             _serverIdleTime = timeout;
 
-            Ice.Properties properties = _instance.initializationData().properties;
-
             string programName = properties.getProperty("Ice.ProgramName");
             if(programName.Length > 0)
             {
@@ -209,16 +209,16 @@ namespace IceInternal
                 _priority = IceInternal.Util.stringToThreadPriority(properties.getProperty("Ice.ThreadPriority"));
             }
 #endif
-            
+
             if(_instance.traceLevels().threadPool >= 1)
             {
-                string s = "creating " + _prefix + ": Size = " + _size + ", SizeMax = " + _sizeMax + ", SizeWarn = " + 
+                string s = "creating " + _prefix + ": Size = " + _size + ", SizeMax = " + _sizeMax + ", SizeWarn = " +
                            _sizeWarn;
                 _instance.initializationData().logger.trace(_instance.traceLevels().threadPoolCat, s);
             }
 
             _workItems = new Queue<ThreadPoolWorkItem>();
-            
+
             try
             {
                 _threads = new List<WorkerThread>();
@@ -251,15 +251,14 @@ namespace IceInternal
             }
         }
 
-        public void updateObservers()
+        public void destroy()
         {
             _m.Lock();
             try
             {
-                foreach(WorkerThread t in _threads)
-                {
-                    t.updateObserver();
-                }
+                Debug.Assert(!_destroyed);
+                _destroyed = true;
+                _m.NotifyAll();
             }
             finally
             {
@@ -267,14 +266,15 @@ namespace IceInternal
             }
         }
 
-        public void destroy()
+        public void updateObservers()
         {
             _m.Lock();
             try
             {
-                Debug.Assert(!_destroyed);
-                _destroyed = true;
-                _m.NotifyAll();
+                foreach(WorkerThread t in _threads)
+                {
+                    t.updateObserver();
+                }
             }
             finally
             {
@@ -298,8 +298,21 @@ namespace IceInternal
             try
             {
                 Debug.Assert(!_destroyed);
-                handler._registered = handler._registered & ~remove;
-                handler._registered = handler._registered | add;
+
+                // Don't remove what needs to be added
+                remove &= ~add;
+
+                // Don't remove/add if already un-registered or registered
+                remove &= handler._registered;
+                add &= ~handler._registered;
+                if(remove == add)
+                {
+                    return;
+                }
+
+                handler._registered &= ~remove;
+                handler._registered |= add;
+
                 if((add & SocketOperation.Read) != 0 && (handler._pending & SocketOperation.Read) == 0)
                 {
                     handler._pending |= SocketOperation.Read;
@@ -314,7 +327,7 @@ namespace IceInternal
                     executeNonBlocking(delegate()
                                        {
                                            messageCallback(new ThreadPoolCurrent(this, handler, SocketOperation.Write));
-                                       }); 
+                                       });
                 }
             }
             finally
@@ -334,12 +347,16 @@ namespace IceInternal
             try
             {
                 Debug.Assert(!_destroyed);
+
+                //
+                // If there are no pending asynchronous operations, we can call finish on the handler now.
+                //
                 if(handler._pending == 0)
                 {
                     handler._registered = SocketOperation.None;
                     executeNonBlocking(delegate()
                                        {
-                                           ThreadPoolCurrent current = 
+                                           ThreadPoolCurrent current =
                                                new ThreadPoolCurrent(this, handler, SocketOperation.None);
                                            handler.finished(ref current);
                                        });
@@ -382,8 +399,7 @@ namespace IceInternal
             }
         }
 
-        public void
-        execute(ThreadPoolWorkItem workItem)
+        public void execute(ThreadPoolWorkItem workItem)
         {
             _m.Lock();
             try
@@ -397,10 +413,10 @@ namespace IceInternal
 
                 //
                 // If this is a dynamic thread pool which can still grow and if all threads are
-                // currently busy dispatching or about to dispatch, we spawn a new thread to 
+                // currently busy dispatching or about to dispatch, we spawn a new thread to
                 // execute this new work item right away.
                 //
-                if(_threads.Count < _sizeMax && 
+                if(_threads.Count < _sizeMax &&
                    (_inUse + _workItems.Count) > _threads.Count &&
                    !_destroyed)
                 {
@@ -409,7 +425,7 @@ namespace IceInternal
                         string s = "growing " + _prefix + ": Size = " + (_threads.Count + 1);
                         _instance.initializationData().logger.trace(_instance.traceLevels().threadPoolCat, s);
                     }
-                    
+
                     try
                     {
                         WorkerThread t = new WorkerThread(this, _threadPrefix + "-" + _threadIndex++);
@@ -440,8 +456,7 @@ namespace IceInternal
             }
         }
 
-        public void
-        executeNonBlocking(ThreadPoolWorkItem workItem)
+        public void executeNonBlocking(ThreadPoolWorkItem workItem)
         {
             _m.Lock();
             try
@@ -519,9 +534,9 @@ namespace IceInternal
                                 {
                                     //
                                     // If not the last thread or if server idle time isn't configured,
-                                    // we can exit. Unlike C++/Java, there's no need to have a thread 
+                                    // we can exit. Unlike C++/Java, there's no need to have a thread
                                     // always spawned in the thread pool because all the IO is done
-                                    // by the .NET thread pool threads. Instead, we'll just spawn a 
+                                    // by the .NET thread pool threads. Instead, we'll just spawn a
                                     // new thread when needed (i.e.: when a new work item is queued).
                                     //
                                     if(_instance.traceLevels().threadPool >= 1)
@@ -530,7 +545,7 @@ namespace IceInternal
                                         _instance.initializationData().logger.trace(
                                             _instance.traceLevels().threadPoolCat, s);
                                     }
-                                    
+
                                     _threads.Remove(thread);
                                     _instance.asyncIOThread().queue(delegate()
                                                                     {
@@ -573,13 +588,13 @@ namespace IceInternal
                     ++_inUse;
 
                     thread.setState(Ice.Instrumentation.ThreadState.ThreadStateInUseForUser);
-                    
+
                     if(_sizeMax > 1 && _inUse == _sizeWarn)
                     {
                         string s = "thread pool `" + _prefix + "' is running low on threads\n"
                             + "Size=" + _size + ", " + "SizeMax=" + _sizeMax + ", " + "SizeWarn=" + _sizeWarn;
                         _instance.initializationData().logger.warning(s);
-                    }                    
+                    }
                 }
                 finally
                 {
@@ -597,11 +612,11 @@ namespace IceInternal
                 }
             }
         }
-    
+
         public bool startMessage(ref ThreadPoolCurrent current)
         {
             Debug.Assert((current._handler._pending & current.operation) != 0);
-                                     
+
             if((current._handler._started & current.operation) != 0)
             {
                 Debug.Assert((current._handler._ready & current.operation) == 0);
@@ -617,7 +632,7 @@ namespace IceInternal
                     return false;
                 }
             }
-            else if((current._handler._ready & current.operation) == 0 && 
+            else if((current._handler._ready & current.operation) == 0 &&
                     (current._handler._registered & current.operation) != 0)
             {
                 Debug.Assert((current._handler._started & current.operation) == 0);
@@ -638,7 +653,7 @@ namespace IceInternal
                     return false;
                 }
             }
-                                     
+
             if((current._handler._registered & current.operation) != 0)
             {
                 Debug.Assert((current._handler._ready & current.operation) != 0);
@@ -700,7 +715,7 @@ namespace IceInternal
         {
             messageCallback(new ThreadPoolCurrent(this, (EventHandler)state, SocketOperation.Read));
         }
-        
+
         public void asyncWriteCallback(object state)
         {
             messageCallback(new ThreadPoolCurrent(this, (EventHandler)state, SocketOperation.Write));
@@ -721,7 +736,7 @@ namespace IceInternal
             {
                 string s = "exception in `" + _prefix + "':\n" + ex + "\nevent handler: " + current._handler.ToString();
                 _instance.initializationData().logger.error(s);
-            }            
+            }
         }
 
         private AsyncCallback getCallback(int operation)
@@ -772,8 +787,7 @@ namespace IceInternal
                 }
             }
 
-            public void
-            setState(Ice.Instrumentation.ThreadState s)
+            public void setState(Ice.Instrumentation.ThreadState s)
             {
                 // Must be called with the thread pool mutex locked
                 if(_observer != null)
@@ -842,7 +856,7 @@ namespace IceInternal
                     string s = "exception in `" + _threadPool._prefix + "' thread " + _thread.Name + ":\n" + ex;
                     _threadPool._instance.initializationData().logger.error(s);
                 }
-                
+
                 if(_observer != null)
                 {
                     _observer.detach();
diff --git a/cs/src/Ice/Transceiver.cs b/cs/src/Ice/Transceiver.cs
index 3e30af51676..c1d887f154d 100644
--- a/cs/src/Ice/Transceiver.cs
+++ b/cs/src/Ice/Transceiver.cs
@@ -14,40 +14,23 @@ namespace IceInternal
 
     public interface Transceiver
     {
-        //
-        // Initialize the transceiver using asynchronous I/O. This method never blocks. Returns true
-        // if initialization is complete, or false if an I/O request is pending. In the latter case,
-        // the callback must invoke initialize again and repeat this process until it returns true.
-        //
-        int initialize();
-
+        int initialize(Buffer readBuffer, Buffer writeBuffer, ref bool hasMoreData);
+        int closing(bool initiator, Ice.LocalException ex);
         void close();
 
-        //
-        // Write data.
-        //
-        // Returns true if all the data was written, false otherwise.
-        //
-        bool write(Buffer buf);
-
-        //
-        // Read data.
-        //
-        // Returns true if all the requested data was read, false otherwise.
-        //
-        bool read(Buffer buf);
+        int write(Buffer buf);
+        int read(Buffer buf, ref bool hasMoreData);
 
         //
         // Read data asynchronously.
         //
-        // The I/O request may complete synchronously, in which case endRead
-        // will be invoked in the same thread as beginRead. The return value
-        // from beginRead must be passed to endRead, along with the same buffer
-        // object. The caller must check the buffer after endRead completes to
-        // determine whether all of the requested data has been read.
+        // The I/O request may complete synchronously, in which case finishRead
+        // will be invoked in the same thread as startRead. The caller must check
+        // the buffer after finishRead completes to determine whether all of the
+        // requested data has been read.
         //
         // The read request is canceled upon the termination of the thread that
-        // calls beginRead, or when the socket is closed. In this case endRead
+        // calls startRead, or when the socket is closed. In this case finishRead
         // raises ReadAbortedException.
         //
         bool startRead(Buffer buf, AsyncCallback callback, object state);
@@ -56,14 +39,14 @@ namespace IceInternal
         //
         // Write data asynchronously.
         //
-        // The I/O request may complete synchronously, in which case endWrite
-        // will be invoked in the same thread as beginWrite. The request
-        // will be canceled upon the termination of the thread that calls beginWrite.
+        // The I/O request may complete synchronously, in which case finishWrite
+        // will be invoked in the same thread as startWrite. The request
+        // will be canceled upon the termination of the thread that calls startWrite.
         //
         bool startWrite(Buffer buf, AsyncCallback callback, object state, out bool completed);
         void finishWrite(Buffer buf);
 
-        string type();
+        string protocol();
         Ice.ConnectionInfo getInfo();
         void checkSendSize(Buffer buf, int messageSizeMax);
     }
diff --git a/cs/src/Ice/UdpConnector.cs b/cs/src/Ice/UdpConnector.cs
index b09cb166b89..e6fddc7044d 100644
--- a/cs/src/Ice/UdpConnector.cs
+++ b/cs/src/Ice/UdpConnector.cs
@@ -18,20 +18,21 @@ namespace IceInternal
     {
         public Transceiver connect()
         {
-            return new UdpTransceiver(instance_, _addr, _mcastInterface, _mcastTtl);
+            return new UdpTransceiver(_instance, _addr, _mcastInterface, _mcastTtl);
         }
 
         public short type()
         {
-            return Ice.UDPEndpointType.value;
+            return _instance.type();
         }
 
         //
-        // Only for use by TcpEndpoint
+        // Only for use by UdpEndpointI
         //
-        internal UdpConnector(Instance instance, EndPoint addr, string mcastInterface, int mcastTtl, string connectionId)
+        internal UdpConnector(ProtocolInstance instance, EndPoint addr, string mcastInterface, int mcastTtl,
+                              string connectionId)
         {
-            instance_ = instance;
+            _instance = instance;
             _addr = addr;
             _mcastInterface = mcastInterface;
             _mcastTtl = mcastTtl;
@@ -85,7 +86,7 @@ namespace IceInternal
             return _hashCode;
         }
 
-        private Instance instance_;
+        private ProtocolInstance _instance;
         private EndPoint _addr;
         private string _mcastInterface;
         private int _mcastTtl;
diff --git a/cs/src/Ice/UdpEndpointI.cs b/cs/src/Ice/UdpEndpointI.cs
index e7a7db586db..921eb60f04f 100644
--- a/cs/src/Ice/UdpEndpointI.cs
+++ b/cs/src/Ice/UdpEndpointI.cs
@@ -17,249 +17,28 @@ namespace IceInternal
     using System;
     using System.Globalization;
 
-    sealed class UdpEndpointI : EndpointI
+    sealed class UdpEndpointI : IPEndpointI
     {
-        public UdpEndpointI(Instance instance, string ho, int po, string mif, int mttl, bool conn, string conId, 
-                            bool co) : base(conId)
+        public UdpEndpointI(ProtocolInstance instance, string ho, int po, string mif, int mttl, bool conn, string conId,
+                            bool co) :
+            base(instance, ho, po, conId)
         {
-            instance_ = instance;
-            _host = ho;
-            _port = po;
             _mcastInterface = mif;
             _mcastTtl = mttl;
             _connect = conn;
-            connectionId_ = conId;
             _compress = co;
-            calcHashValue();
         }
-        
-        public UdpEndpointI(Instance instance, string str, bool oaEndpoint) : base("")
+
+        public UdpEndpointI(ProtocolInstance instance) :
+            base(instance)
         {
-            instance_ = instance;
-            _host = null;
-            _port = 0;
             _connect = false;
             _compress = false;
-
-            string delim = " \t\n\r";
-
-            int beg;
-            int end = 0;
-
-            while(true)
-            {
-                beg = IceUtilInternal.StringUtil.findFirstNotOf(str, delim, end);
-                if(beg == -1)
-                {
-                    break;
-                }
-
-                end = IceUtilInternal.StringUtil.findFirstOf(str, delim, beg);
-                if(end == -1)
-                {
-                    end = str.Length;
-                }
-
-                string option = str.Substring(beg, end - beg);
-                if(option[0] != '-')
-                {
-                    Ice.EndpointParseException e = new Ice.EndpointParseException();
-                    e.str = "expected an endpoint option but found `" + option + "' in endpoint `udp " + str + "'";
-                    throw e;
-                }
-
-                string argument = null;
-                int argumentBeg = IceUtilInternal.StringUtil.findFirstNotOf(str, delim, end);
-                if(argumentBeg != -1 && str[argumentBeg] != '-')
-                {
-                    beg = argumentBeg;
-                    if(str[beg] == '\"')
-                    {
-                        end = IceUtilInternal.StringUtil.findFirstOf(str, "\"", beg + 1);
-                        if(end == -1)
-                        {
-                            Ice.EndpointParseException e = new Ice.EndpointParseException();
-                            e.str = "mismatched quotes around `" + argument + "' in endpoint `udp " + str + "'";
-                            throw e;
-                        }
-                        else
-                        {
-                            ++end;
-                        }
-                    }
-                    else
-                    {
-                        end = IceUtilInternal.StringUtil.findFirstOf(str, delim, beg);
-                        if(end == -1)
-                        {
-                            end = str.Length;
-                        }
-                    }
-                    argument = str.Substring(beg, end - beg);
-                    if(argument[0] == '\"' && argument[argument.Length - 1] == '\"')
-                    {
-                        argument = argument.Substring(1, argument.Length - 2);
-                    }
-                }
-                
-                if(option.Equals("-h"))
-                {
-                    if(argument == null)
-                    {
-                        Ice.EndpointParseException e = new Ice.EndpointParseException();
-                        e.str = "no argument provided for -h option in endpoint `udp " + str + "'";
-                        throw e;
-                    }
-                    
-                    _host = argument;
-                }
-                else if(option.Equals("-p"))
-                {
-                    if(argument == null)
-                    {
-                        Ice.EndpointParseException e = new Ice.EndpointParseException();
-                        e.str = "no argument provided for -p option in endpoint `udp " + str + "'";
-                        throw e;
-                    }
-                    
-                    try
-                    {
-                        _port = System.Int32.Parse(argument, CultureInfo.InvariantCulture);
-                    }
-                    catch(System.FormatException ex)
-                    {
-                        Ice.EndpointParseException e = new Ice.EndpointParseException(ex);
-                        e.str = "invalid port value `" + argument + "' in endpoint `udp " + str + "'";
-                        throw e;
-                    }
-
-                    if(_port < 0 || _port > 65535)
-                    {
-                        Ice.EndpointParseException e = new Ice.EndpointParseException();
-                        e.str = "port value `" + argument + "' out of range in endpoint `udp " + str + "'";
-                        throw e;
-                    }
-                }
-                else if(option.Equals("-c"))
-                {
-                    if(argument != null)
-                    {
-                        Ice.EndpointParseException e = new Ice.EndpointParseException();
-                        e.str = "unexpected argument `" + argument + "' provided for -c option in `udp " + str + "'";
-                        throw e;
-                    }
-                    
-                    _connect = true;
-                }
-                else if(option.Equals("-z"))
-                {
-                    if(argument != null)
-                    {
-                        Ice.EndpointParseException e = new Ice.EndpointParseException();
-                        e.str = "unexpected argument `" + argument + "' provided for -z option in `udp " + str + "'";
-                        throw e;
-                    }
-                    
-                    _compress = true;
-                }
-                else if(option.Equals("-v") || option.Equals("-e"))
-                {
-                    if(argument == null)
-                    {
-                        Ice.EndpointParseException e = new Ice.EndpointParseException();
-                        e.str = "no argument provided for " + option + " option in endpoint " + "`udp " + str + "'";
-                        throw e;
-                    }
-
-                    try
-                    {
-                        Ice.EncodingVersion v = Ice.Util.stringToEncodingVersion(argument);
-                        if(v.major != 1 || v.minor != 0)
-                        {
-                            instance_.initializationData().logger.warning("deprecated udp endpoint option: " + option);
-                        }
-                    }
-                    catch(Ice.VersionParseException ex)
-                    {
-                        Ice.EndpointParseException e = new Ice.EndpointParseException();
-                        e.str = "invalid version `" + argument + "' in endpoint `udp " + str + "':\n" + ex.str;
-                        throw e;
-                    }
-                }
-                else if(option.Equals("--interface"))
-                {
-                    if(argument == null)
-                    {
-                        Ice.EndpointParseException e = new Ice.EndpointParseException();
-                        e.str = "no argument provided for --interface option in endpoint `udp " + str + "'";
-                        throw e;
-                    }
-                    
-                    _mcastInterface = argument;
-                }
-                else if(option.Equals("--ttl"))
-                {
-                    if(argument == null)
-                    {
-                        Ice.EndpointParseException e = new Ice.EndpointParseException();
-                        e.str = "no argument provided for --ttl option in endpoint `udp " + str + "'";
-                        throw e;
-                    }
-                    
-                    try
-                    {
-                        _mcastTtl = System.Int32.Parse(argument, CultureInfo.InvariantCulture);
-                    }
-                    catch(System.FormatException ex)
-                    {
-                        Ice.EndpointParseException e = new Ice.EndpointParseException(ex);
-                        e.str = "invalid TTL value `" + argument + "' in endpoint `udp " + str + "'";
-                        throw e;
-                    }
-
-                    if(_mcastTtl < 0)
-                    {
-                        Ice.EndpointParseException e = new Ice.EndpointParseException();
-                        e.str = "TTL value `" + argument + "' out of range in endpoint `udp " + str + "'";
-                        throw e;
-                    }
-                }
-                else
-                {
-                    throw new Ice.EndpointParseException("unknown option `" + option + "' in endpoint `udp " + str + "'");
-                }
-            }
-
-            if(_host == null)
-            {
-                _host = instance_.defaultsAndOverrides().defaultHost;
-            }
-            else if(_host.Equals("*"))
-            {
-                if(oaEndpoint)
-                {
-                    _host = null;
-                }
-                else
-                {
-                    throw new Ice.EndpointParseException("`-h *' not valid for proxy endpoint `udp " + str + "'");
-                }        
-            }
-
-            if(_host == null)
-            {
-                _host = "";
-            }
-            
-            calcHashValue();
         }
-        
-        public UdpEndpointI(BasicStream s)
+
+        public UdpEndpointI(ProtocolInstance instance, BasicStream s) :
+            base(instance, s)
         {
-            instance_ = s.instance();
-            s.startReadEncaps();
-            _host = s.readString();
-            _port = s.readInt();
             if(s.getReadEncoding().Equals(Ice.Util.Encoding_1_0))
             {
                 s.readByte();
@@ -271,140 +50,62 @@ namespace IceInternal
             //_connect = s.readBool();
             _connect = false;
             _compress = s.readBool();
-            s.endReadEncaps();
-            calcHashValue();
         }
-        
-        //
-        // Marshal the endpoint
-        //
-        public override void streamWrite(BasicStream s)
-        {
-            s.writeShort(Ice.UDPEndpointType.value);
-            s.startWriteEncaps();
-            s.writeString(_host);
-            s.writeInt(_port);
-            if(s.getWriteEncoding().Equals(Ice.Util.Encoding_1_0))
-            {
-                Ice.Util.Protocol_1_0.write__(s);
-                Ice.Util.Encoding_1_0.write__(s);
-            }
-            // Not transmitted.
-            //s.writeBool(_connect);
-            s.writeBool(_compress);
-            s.endWriteEncaps();
-        }
-        
-        //
-        // Convert the endpoint to its string form
-        //
-        public override string ice_toString_()
-        {
-            //
-            // WARNING: Certain features, such as proxy validation in Glacier2,
-            // depend on the format of proxy strings. Changes to toString() and
-            // methods called to generate parts of the reference string could break
-            // these features. Please review for all features that depend on the
-            // format of proxyToString() before changing this and related code.
-            //
-            string s = "udp";
-
-            if(_host != null && _host.Length != 0)
-            {
-                s += " -h ";
-                bool addQuote = _host.IndexOf(':') != -1;
-                if(addQuote)
-                {
-                    s += "\"";
-                }
-                s += _host;
-                if(addQuote)
-                {
-                    s += "\"";
-                }
-            }
-
-            s += " -p " + _port;
-
-            if(_mcastInterface.Length != 0)
-            {
-                s += " --interface " + _mcastInterface;
-            }
-
-            if(_mcastTtl != -1)
-            {
-                s += " --ttl " + _mcastTtl;
-            }
-
-            if(_connect)
-            {
-                s += " -c";
-            }
 
-            if(_compress)
-            {
-                s += " -z";
-            }
-
-            return s;
-        }
-        
         private sealed class InfoI : Ice.UDPEndpointInfo
         {
-            public InfoI(bool comp, string host, int port, string mcastInterface, int mcastTtl) :
-                base(-1, comp, host, port, mcastInterface, mcastTtl)
+            public InfoI(UdpEndpointI e)
             {
+                _endpoint = e;
             }
 
             override public short type()
             {
-                return Ice.UDPEndpointType.value;
+                return _endpoint.type();
             }
-                
+
             override public bool datagram()
             {
-                return true;
+                return _endpoint.datagram();
             }
-                
+
             override public bool secure()
             {
-                return false;
+                return _endpoint.secure();
             }
-        };
+
+            private UdpEndpointI _endpoint;
+        }
 
         //
         // Return the endpoint information.
         //
         public override Ice.EndpointInfo getInfo()
         {
-            return new InfoI(_compress, _host, _port, _mcastInterface, _mcastTtl);
+            InfoI info = new InfoI(this);
+            fillEndpointInfo(info);
+            return info;
         }
 
         //
-        // Return the endpoint type
-        //
-        public override short type()
-        {
-            return Ice.UDPEndpointType.value;
-        }
-        
-        //
-        // Return the protocol name;
+        // Return the timeout for the endpoint in milliseconds. 0 means
+        // non-blocking, -1 means no timeout.
         //
-        public override string protocol()
+        public override int timeout()
         {
-            return "udp";
+            return -1;
         }
 
         //
-        // Return the timeout for the endpoint in milliseconds. 0 means
-        // non-blocking, -1 means no timeout.
+        // Return a new endpoint with a different timeout value, provided
+        // that timeouts are supported by the endpoint. Otherwise the same
+        // endpoint is returned.
         //
-        public override int timeout()
+        public override EndpointI timeout(int timeout)
         {
-            return -1;
+            return this;
         }
-        
+
         //
         // Return true if the endpoints support bzip2 compress, or false
         // otherwise.
@@ -413,7 +114,7 @@ namespace IceInternal
         {
             return _compress;
         }
-        
+
         //
         // Return a new endpoint with a different compression value,
         // provided that compression is supported by the
@@ -427,45 +128,19 @@ namespace IceInternal
             }
             else
             {
-                return new UdpEndpointI(instance_, _host, _port, _mcastInterface, _mcastTtl, _connect, connectionId_, 
+                return new UdpEndpointI(instance_, host_, port_, _mcastInterface, _mcastTtl, _connect, connectionId_,
                                         compress);
             }
         }
 
         //
-        // Return a new endpoint with a different connection id.
-        //
-        public override EndpointI connectionId(string connectionId)
-        {
-            if(connectionId == connectionId_)
-            {
-                return this;
-            }
-            else
-            {
-                return new UdpEndpointI(instance_, _host, _port, _mcastInterface, _mcastTtl, _connect, connectionId, 
-                                        _compress);
-            }
-        }
-        
-        //
-        // Return a new endpoint with a different timeout value, provided
-        // that timeouts are supported by the endpoint. Otherwise the same
-        // endpoint is returned.
-        //
-        public override EndpointI timeout(int timeout)
-        {
-            return this;
-        }
-        
-        //
         // Return true if the endpoint is datagram-based.
         //
         public override bool datagram()
         {
             return true;
         }
-        
+
         //
         // Return true if the endpoint is secure.
         //
@@ -483,34 +158,12 @@ namespace IceInternal
         //
         public override Transceiver transceiver(ref EndpointI endpoint)
         {
-            UdpTransceiver p = new UdpTransceiver(instance_, _host, _port, _mcastInterface, _connect);
-            endpoint = new UdpEndpointI(instance_, _host, p.effectivePort(), _mcastInterface, _mcastTtl, 
-                                        _connect, connectionId_, _compress);
+            UdpTransceiver p = new UdpTransceiver(instance_, host_, port_, _mcastInterface, _connect);
+            endpoint = createEndpoint(host_, p.effectivePort(), connectionId_);
             return p;
         }
 
         //
-        // Return a connector for this endpoint, or empty list if no connector
-        // is available.
-        //
-        public override List<Connector> connectors(Ice.EndpointSelectionType selType)
-        {
-            return connectors(Network.getAddresses(_host, _port, instance_.protocolSupport(), selType,
-                                                   instance_.preferIPv6(), true),
-                              instance_.networkProxy());
-        }
-
-
-        public override void connectors_async(Ice.EndpointSelectionType selType, EndpointI_connectors callback)
-        {
-#if SILVERLIGHT
-            callback.connectors(connectors(selType));
-#else
-            instance_.endpointHostResolver().resolve(_host, _port, selType, this, callback);
-#endif
-        }
-        
-        //
         // Return an acceptor for this endpoint, or null if no acceptors
         // is available. In case an acceptor is created, this operation
         // also returns a new "effective" endpoint, which might differ
@@ -523,59 +176,40 @@ namespace IceInternal
             return null;
         }
 
-        //
-        // Expand endpoint out in to separate endpoints for each local
-        // host if listening on INADDR_ANY.
-        //
-        public override List<EndpointI>
-        expand()
+        public override string options()
         {
-            List<EndpointI> endps = new List<EndpointI>();
-            List<string> hosts = Network.getHostsForEndpointExpand(_host, instance_.protocolSupport(), false);
-            if(hosts == null || hosts.Count == 0)
+            //
+            // WARNING: Certain features, such as proxy validation in Glacier2,
+            // depend on the format of proxy strings. Changes to toString() and
+            // methods called to generate parts of the reference string could break
+            // these features. Please review for all features that depend on the
+            // format of proxyToString() before changing this and related code.
+            //
+            string s = base.options();
+
+            if(_mcastInterface.Length != 0)
             {
-                endps.Add(this);
+                s += " --interface " + _mcastInterface;
             }
-            else
+
+            if(_mcastTtl != -1)
             {
-                foreach(string h in hosts)
-                {
-                    endps.Add(new UdpEndpointI(instance_, h, _port, _mcastInterface, _mcastTtl, _connect, 
-                                               connectionId_, _compress));
-                }
+                s += " --ttl " + _mcastTtl;
             }
-            return endps;
-        }
 
-        //
-        // Check whether the endpoint is equivalent to another one.
-        //
-        public override bool equivalent(EndpointI endpoint)
-        {
-            if(!(endpoint is UdpEndpointI))
+            if(_connect)
             {
-                return false;
+                s += " -c";
             }
 
-            UdpEndpointI udpEndpointI = (UdpEndpointI)endpoint;
-            return udpEndpointI._host.Equals(_host) && udpEndpointI._port == _port;
-        }
-
-        public override List<Connector> connectors(List<EndPoint> addresses, NetworkProxy networkProxy)
-        {
-            List<Connector> connectors = new List<Connector>();
-            foreach(EndPoint addr in addresses)
+            if(_compress)
             {
-                connectors.Add(new UdpConnector(instance_, addr, _mcastInterface, _mcastTtl, connectionId_));
+                s += " -z";
             }
-            return connectors;
-        }
 
-        public override int GetHashCode()
-        {
-            return _hashCode;
+            return s;
         }
-        
+
         //
         // Compare endpoints for sorting purposes
         //
@@ -591,24 +225,7 @@ namespace IceInternal
             {
                 return 0;
             }
-            else
-            {
-                int r = base.CompareTo(p);
-                if(r != 0)
-                {
-                    return r;
-                }
-            }
-            
-            if(_port < p._port)
-            {
-                return -1;
-            }
-            else if(p._port < _port)
-            {
-                return 1;
-            }
-            
+
             if(!_connect && p._connect)
             {
                 return -1;
@@ -617,11 +234,6 @@ namespace IceInternal
             {
                 return 1;
             }
-            
-            if(!connectionId_.Equals(p.connectionId_))
-            {
-                return string.Compare(connectionId_, p.connectionId_, StringComparison.Ordinal);
-            }
 
             if(!_compress && p._compress)
             {
@@ -631,13 +243,13 @@ namespace IceInternal
             {
                 return 1;
             }
-            
+
             int rc = string.Compare(_mcastInterface, p._mcastInterface, StringComparison.Ordinal);
             if(rc != 0)
             {
                 return rc;
             }
-            
+
             if(_mcastTtl < p._mcastTtl)
             {
                 return -1;
@@ -647,66 +259,203 @@ namespace IceInternal
                 return 1;
             }
 
-            return string.Compare(_host, p._host, StringComparison.Ordinal);
+            return base.CompareTo(p);
         }
-        
-        private void calcHashValue()
+
+        //
+        // Marshal the endpoint
+        //
+        protected override void streamWriteImpl(BasicStream s)
         {
-            int h = 5381;
-            IceInternal.HashUtil.hashAdd(ref h, Ice.UDPEndpointType.value);
-            IceInternal.HashUtil.hashAdd(ref h, _host);
-            IceInternal.HashUtil.hashAdd(ref h, _port);
+            base.streamWriteImpl(s);
+            if(s.getWriteEncoding().Equals(Ice.Util.Encoding_1_0))
+            {
+                Ice.Util.Protocol_1_0.write__(s);
+                Ice.Util.Encoding_1_0.write__(s);
+            }
+            // Not transmitted.
+            //s.writeBool(_connect);
+            s.writeBool(_compress);
+        }
+
+        protected override void hashInit(ref int h)
+        {
+            base.hashInit(ref h);
             IceInternal.HashUtil.hashAdd(ref h, _mcastInterface);
             IceInternal.HashUtil.hashAdd(ref h, _mcastTtl);
             IceInternal.HashUtil.hashAdd(ref h, _connect);
-            IceInternal.HashUtil.hashAdd(ref h, connectionId_);
             IceInternal.HashUtil.hashAdd(ref h, _compress);
-            _hashCode = h;
         }
-        
-        private Instance instance_;
-        private string _host;
-        private int _port;
+
+        protected override void fillEndpointInfo(Ice.IPEndpointInfo info)
+        {
+            base.fillEndpointInfo(info);
+            if(info is Ice.UDPEndpointInfo)
+            {
+                Ice.UDPEndpointInfo udpInfo = (Ice.UDPEndpointInfo)info;
+                udpInfo.timeout = -1;
+                udpInfo.compress = _compress;
+                udpInfo.mcastInterface = _mcastInterface;
+                udpInfo.mcastTtl = _mcastTtl;
+            }
+        }
+
+        protected override bool checkOption(string option, string argument, string endpoint)
+        {
+            if(base.checkOption(option, argument, endpoint))
+            {
+                return true;
+            }
+
+            if(option.Equals("-c"))
+            {
+                if(argument != null)
+                {
+                    Ice.EndpointParseException e = new Ice.EndpointParseException();
+                    e.str = "unexpected argument `" + argument + "' provided for -c option in " + endpoint;
+                    throw e;
+                }
+
+                _connect = true;
+            }
+            else if(option.Equals("-z"))
+            {
+                if(argument != null)
+                {
+                    Ice.EndpointParseException e = new Ice.EndpointParseException();
+                    e.str = "unexpected argument `" + argument + "' provided for -z option in " + endpoint;
+                    throw e;
+                }
+
+                _compress = true;
+            }
+            else if(option.Equals("-v") || option.Equals("-e"))
+            {
+                if(argument == null)
+                {
+                    Ice.EndpointParseException e = new Ice.EndpointParseException();
+                    e.str = "no argument provided for " + option + " option in endpoint " + endpoint;
+                    throw e;
+                }
+
+                try
+                {
+                    Ice.EncodingVersion v = Ice.Util.stringToEncodingVersion(argument);
+                    if(v.major != 1 || v.minor != 0)
+                    {
+                        instance_.logger().warning("deprecated udp endpoint option: " + option);
+                    }
+                }
+                catch(Ice.VersionParseException ex)
+                {
+                    Ice.EndpointParseException e = new Ice.EndpointParseException();
+                    e.str = "invalid version `" + argument + "' in endpoint " + endpoint + ":\n" + ex.str;
+                    throw e;
+                }
+            }
+            else if(option.Equals("--interface"))
+            {
+                if(argument == null)
+                {
+                    Ice.EndpointParseException e = new Ice.EndpointParseException();
+                    e.str = "no argument provided for --interface option in endpoint " + endpoint;
+                    throw e;
+                }
+
+                _mcastInterface = argument;
+            }
+            else if(option.Equals("--ttl"))
+            {
+                if(argument == null)
+                {
+                    Ice.EndpointParseException e = new Ice.EndpointParseException();
+                    e.str = "no argument provided for --ttl option in endpoint " + endpoint;
+                    throw e;
+                }
+
+                try
+                {
+                    _mcastTtl = System.Int32.Parse(argument, CultureInfo.InvariantCulture);
+                }
+                catch(System.FormatException ex)
+                {
+                    Ice.EndpointParseException e = new Ice.EndpointParseException(ex);
+                    e.str = "invalid TTL value `" + argument + "' in endpoint " + endpoint;
+                    throw e;
+                }
+
+                if(_mcastTtl < 0)
+                {
+                    Ice.EndpointParseException e = new Ice.EndpointParseException();
+                    e.str = "TTL value `" + argument + "' out of range in endpoint " + endpoint;
+                    throw e;
+                }
+            }
+            else
+            {
+                return false;
+            }
+
+            return true;
+        }
+
+        protected override Connector createConnector(EndPoint addr, NetworkProxy proxy)
+        {
+            return new UdpConnector(instance_, addr, _mcastInterface, _mcastTtl, connectionId_);
+        }
+
+        protected override IPEndpointI createEndpoint(string host, int port, string connectionId)
+        {
+            return new UdpEndpointI(instance_, host, port, _mcastInterface, _mcastTtl, _connect, connectionId,
+                                    _compress);
+        }
+
         private string _mcastInterface = "";
         private int _mcastTtl = -1;
         private bool _connect;
         private bool _compress;
-        private int _hashCode;
     }
 
     sealed class UdpEndpointFactory : EndpointFactory
     {
-        internal UdpEndpointFactory(Instance instance)
+        internal UdpEndpointFactory(ProtocolInstance instance)
         {
-            instance_ = instance;
+            _instance = instance;
         }
-        
+
         public short type()
         {
-            return Ice.UDPEndpointType.value;
+            return _instance.type();
         }
-        
+
         public string protocol()
         {
-            return "udp";
+            return _instance.protocol();
         }
-        
-        public EndpointI create(string str, bool oaEndpoint)
+
+        public EndpointI create(List<string> args, bool oaEndpoint)
         {
-            return new UdpEndpointI(instance_, str, oaEndpoint);
+            IPEndpointI endpt = new UdpEndpointI(_instance);
+            endpt.initWithOptions(args, oaEndpoint);
+            return endpt;
         }
-        
+
         public EndpointI read(BasicStream s)
         {
-            return new UdpEndpointI(s);
+            return new UdpEndpointI(_instance, s);
         }
-        
+
         public void destroy()
         {
-            instance_ = null;
+            _instance = null;
         }
-        
-        private Instance instance_;
+
+        public EndpointFactory clone(ProtocolInstance instance)
+        {
+            return new UdpEndpointFactory(instance);
+        }
+
+        private ProtocolInstance _instance;
     }
 
 }
diff --git a/cs/src/Ice/UdpTransceiver.cs b/cs/src/Ice/UdpTransceiver.cs
index 550b5c6f380..292ea96d4fc 100644
--- a/cs/src/Ice/UdpTransceiver.cs
+++ b/cs/src/Ice/UdpTransceiver.cs
@@ -27,7 +27,7 @@ namespace IceInternal
 
     sealed class UdpTransceiver : Transceiver
     {
-        public int initialize()
+        public int initialize(Buffer readBuffer, Buffer writeBuffer, ref bool hasMoreData)
         {
             if(_state == StateNeedConnect)
             {
@@ -61,7 +61,7 @@ namespace IceInternal
                 {
                     //
                     // On Windows, we delay the join for the mcast group after the connection
-                    // establishment succeeds. This is necessary for older Windows versions 
+                    // establishment succeeds. This is necessary for older Windows versions
                     // where joining the group fails if the socket isn't bound. See ICE-5113.
                     //
                     if(Network.isMulticast((IPEndPoint)_addr))
@@ -73,16 +73,16 @@ namespace IceInternal
                         }
                     }
                 }
-#endif                    
+#endif
                 _state = StateConnected;
             }
 
             if(_state == StateConnected)
             {
-                if(_traceLevels.network >= 1)
+                if(_instance.traceLevel() >= 1)
                 {
-                    string s = "starting to send udp packets\n" + ToString();
-                    _logger.trace(_traceLevels.networkCat, s);
+                    string s = "starting to send " + protocol() + " packets\n" + ToString();
+                    _instance.logger().trace(_instance.traceCategory(), s);
                 }
                 Debug.Assert(_state == StateConnected);
             }
@@ -90,14 +90,22 @@ namespace IceInternal
             return SocketOperation.None;
         }
 
+        public int closing(bool initiator, Ice.LocalException ex)
+        {
+            //
+            // Nothing to do.
+            //
+            return SocketOperation.None;
+        }
+
         public void close()
         {
-            if(_state >= StateConnected && _traceLevels.network >= 1)
+            if(_state >= StateConnected && _instance.traceLevel() >= 1)
             {
-                string s = "closing udp connection\n" + ToString();
-                _logger.trace(_traceLevels.networkCat, s);
+                string s = "closing " + protocol() + " connection\n" + ToString();
+                _instance.logger().trace(_instance.traceCategory(), s);
             }
-            
+
             if(_fd != null)
             {
                 try
@@ -111,16 +119,21 @@ namespace IceInternal
             }
         }
 
-        public bool write(Buffer buf)
+        public int write(Buffer buf)
         {
 #if COMPACT || SILVERLIGHT
             //
             // Silverlight and the Compact .NET Framework don't support the use of synchronous socket
-            // operations on a non-blocking socket. Returning false here forces the
+            // operations on a non-blocking socket. Returning SocketOperation.Write here forces the
             // caller to schedule an asynchronous operation.
             //
-            return false;
+            return SocketOperation.Write;
 #else
+            if(!buf.b.hasRemaining())
+            {
+                return SocketOperation.None;
+            }
+
             Debug.Assert(buf.b.position() == 0);
             Debug.Assert(_fd != null && _state >= StateConnected);
 
@@ -152,10 +165,10 @@ namespace IceInternal
                     {
                         continue;
                     }
-                    
+
                     if(Network.wouldBlock(ex))
                     {
-                        return false;
+                        return SocketOperation.Write;
                     }
 
                     if(Network.connectionLost(ex))
@@ -174,27 +187,33 @@ namespace IceInternal
             }
 
             Debug.Assert(ret > 0);
-            
-            if(_traceLevels.network >= 3)
+
+            if(_instance.traceLevel() >= 3)
             {
-                string s = "sent " + ret + " bytes via udp\n" + ToString();
-                _logger.trace(_traceLevels.networkCat, s);
+                string s = "sent " + ret + " bytes via " + protocol() + "\n" + ToString();
+                _instance.logger().trace(_instance.traceCategory(), s);
             }
+
             Debug.Assert(ret == buf.b.limit());
-            return true;
+            return SocketOperation.None;
 #endif
         }
 
-        public bool read(Buffer buf)
+        public int read(Buffer buf, ref bool hasMoreData)
         {
 #if COMPACT || SILVERLIGHT
             //
             // Silverlight and the Compact .NET Framework don't support the use of synchronous socket
-            // operations on a non-blocking socket. Returning false here forces the
+            // operations on a non-blocking socket. Returning SocketOperation.Read here forces the
             // caller to schedule an asynchronous operation.
             //
-            return false;
+            return SocketOperation.Read;
 #else
+            if(!buf.b.hasRemaining())
+            {
+                return SocketOperation.None;
+            }
+
             Debug.Assert(buf.b.position() == 0);
             Debug.Assert(_fd != null);
 
@@ -236,7 +255,7 @@ namespace IceInternal
                 {
                     if(Network.recvTruncated(e))
                     {
-                        // The message was truncated and the whole buffer is filled. We ignore 
+                        // The message was truncated and the whole buffer is filled. We ignore
                         // this error here, it will be detected at the connection level when
                         // the Ice message size is checked against the buffer size.
                         ret = buf.size();
@@ -247,12 +266,12 @@ namespace IceInternal
                     {
                         continue;
                     }
-                    
+
                     if(Network.wouldBlock(e))
                     {
-                        return false;
+                        return SocketOperation.Read;
                     }
-                    
+
                     if(Network.connectionLost(e))
                     {
                         throw new Ice.ConnectionLostException();
@@ -267,7 +286,7 @@ namespace IceInternal
                     throw new Ice.SyscallException(e);
                 }
             }
-                
+
             if(ret == 0)
             {
                 throw new Ice.ConnectionLostException();
@@ -284,23 +303,23 @@ namespace IceInternal
                 Debug.Assert(connected);
                 _state = StateConnected; // We're connected now
 
-                if(_traceLevels.network >= 1)
+                if(_instance.traceLevel() >= 1)
                 {
-                    string s = "connected udp socket\n" + ToString();
-                    _logger.trace(_traceLevels.networkCat, s);
+                    string s = "connected " + protocol() + " socket\n" + ToString();
+                    _instance.logger().trace(_instance.traceCategory(), s);
                 }
             }
 
-            if(_traceLevels.network >= 3)
+            if(_instance.traceLevel() >= 3)
             {
-                string s = "received " + ret + " bytes via udp\n" + ToString();
-                _logger.trace(_traceLevels.networkCat, s);
+                string s = "received " + ret + " bytes via " + protocol() + "\n" + ToString();
+                _instance.logger().trace(_instance.traceCategory(), s);
             }
 
             buf.resize(ret, true);
             buf.b.position(ret);
 
-            return true;
+            return SocketOperation.None;
 #endif
         }
 
@@ -313,7 +332,7 @@ namespace IceInternal
             buf.b.position(0);
 
             try
-            {                
+            {
                 if(_state == StateConnected)
                 {
                     _readCallback = callback;
@@ -322,7 +341,7 @@ namespace IceInternal
                     _readEventArgs.SetBuffer(buf.b.rawBytes(), buf.b.position(), packetSize);
                     return !_fd.ReceiveAsync(_readEventArgs);
 #else
-                    _readResult = _fd.BeginReceive(buf.b.rawBytes(), 0, buf.b.limit(), SocketFlags.None, 
+                    _readResult = _fd.BeginReceive(buf.b.rawBytes(), 0, buf.b.limit(), SocketFlags.None,
                                                    readCompleted, state);
                     return _readResult.CompletedSynchronously;
 #endif
@@ -349,7 +368,7 @@ namespace IceInternal
                             peerAddr = new IPEndPoint(IPAddress.IPv6Any, 0);
                         }
                     }
-                    _readResult = _fd.BeginReceiveFrom(buf.b.rawBytes(), 0, buf.b.limit(), SocketFlags.None, 
+                    _readResult = _fd.BeginReceiveFrom(buf.b.rawBytes(), 0, buf.b.limit(), SocketFlags.None,
                                                        ref peerAddr, readCompleted, state);
                     return _readResult.CompletedSynchronously;
 #endif
@@ -424,7 +443,7 @@ namespace IceInternal
             {
                 if(Network.recvTruncated(ex))
                 {
-                    // The message was truncated and the whole buffer is filled. We ignore 
+                    // The message was truncated and the whole buffer is filled. We ignore
                     // this error here, it will be detected at the connection level when
                     // the Ice message size is checked against the buffer size.
                     ret = buf.size();
@@ -435,7 +454,7 @@ namespace IceInternal
                     {
                         throw new Ice.ConnectionLostException(ex);
                     }
-                    
+
                     if(Network.connectionRefused(ex))
                     {
                         throw new Ice.ConnectionRefusedException(ex);
@@ -470,17 +489,17 @@ namespace IceInternal
                 Debug.Assert(connected);
                 _state = StateConnected; // We're connected now
 
-                if(_traceLevels.network >= 1)
+                if(_instance.traceLevel() >= 1)
                 {
                     string s = "connected udp socket\n" + ToString();
-                    _logger.trace(_traceLevels.networkCat, s);
+                    _instance.logger().trace(_instance.traceCategory(), s);
                 }
             }
 
-            if(_traceLevels.network >= 3)
+            if(_instance.traceLevel() >= 3)
             {
                 string s = "received " + ret + " bytes via udp\n" + ToString();
-                _logger.trace(_traceLevels.networkCat, s);
+                _instance.logger().trace(_instance.traceCategory(), s);
             }
 
             buf.resize(ret, true);
@@ -521,7 +540,7 @@ namespace IceInternal
                     _writeEventArgs.SetBuffer(buf.b.rawBytes(), 0, buf.b.limit());
                     completedSynchronously = !_fd.SendAsync(_writeEventArgs);
 #else
-                    _writeResult = _fd.BeginSend(buf.b.rawBytes(), 0, buf.b.limit(), SocketFlags.None, 
+                    _writeResult = _fd.BeginSend(buf.b.rawBytes(), 0, buf.b.limit(), SocketFlags.None,
                                                  writeCompleted, state);
                     completedSynchronously = _writeResult.CompletedSynchronously;
 #endif
@@ -633,25 +652,24 @@ namespace IceInternal
             {
                 throw new Ice.ConnectionLostException();
             }
-            
+
             Debug.Assert(ret > 0);
-            
-            if(_traceLevels.network >= 3)
+
+            if(_instance.traceLevel() >= 3)
             {
                 string s = "sent " + ret + " bytes via udp\n" + ToString();
-                _logger.trace(_traceLevels.networkCat, s);
+                _instance.logger().trace(_instance.traceCategory(), s);
             }
             Debug.Assert(ret == buf.b.limit());
             buf.b.position(buf.b.position() + ret);
         }
 
-        public string type()
+        public string protocol()
         {
-            return "udp";
+            return _instance.protocol();
         }
 
-        public Ice.ConnectionInfo
-        getInfo()
+        public Ice.ConnectionInfo getInfo()
         {
             Ice.UDPConnectionInfo info = new Ice.UDPConnectionInfo();
             if(_fd != null)
@@ -695,7 +713,7 @@ namespace IceInternal
             }
 
             //
-            // The maximum packetSize is either the maximum allowable UDP packet size, or 
+            // The maximum packetSize is either the maximum allowable UDP packet size, or
             // the UDP send buffer size (which ever is smaller).
             //
             int packetSize = System.Math.Min(_maxPacketSize, _sndSize - _udpOverhead);
@@ -730,8 +748,8 @@ namespace IceInternal
             if(_mcastAddr != null)
             {
                 s += "\nmulticast address = " + Network.addrToString(_mcastAddr);
-            }   
-#endif         
+            }
+#endif
             return s;
         }
 
@@ -743,10 +761,9 @@ namespace IceInternal
         //
         // Only for use by UdpConnector.
         //
-        internal UdpTransceiver(Instance instance, EndPoint addr, string mcastInterface, int mcastTtl)
+        internal UdpTransceiver(ProtocolInstance instance, EndPoint addr, string mcastInterface, int mcastTtl)
         {
-            _traceLevels = instance.traceLevels();
-            _logger = instance.initializationData().logger;
+            _instance = instance;
             _addr = addr;
 
 #if ICE_SOCKET_ASYNC_API
@@ -758,7 +775,7 @@ namespace IceInternal
             _writeEventArgs.RemoteEndPoint = _addr;
             _writeEventArgs.Completed += new EventHandler<SocketAsyncEventArgs>(ioCompleted);
 #if SILVERLIGHT
-            String policy = instance.initializationData().properties.getProperty("Ice.ClientAccessPolicyProtocol");
+            String policy = instance.properties().getProperty("Ice.ClientAccessPolicyProtocol");
             if(policy.Equals("Http"))
             {
                 _readEventArgs.SocketClientAccessPolicyProtocol = SocketClientAccessPolicyProtocol.Http;
@@ -766,7 +783,7 @@ namespace IceInternal
             }
             else if(!String.IsNullOrEmpty(policy))
             {
-                _logger.warning("Ignoring invalid Ice.ClientAccessPolicyProtocol value `" + policy + "'");
+                _instance.logger().warning("Ignoring invalid Ice.ClientAccessPolicyProtocol value `" + policy + "'");
             }
 #endif
 #endif
@@ -779,14 +796,14 @@ namespace IceInternal
             try
             {
                 _fd = Network.createSocket(true, _addr.AddressFamily);
-                setBufSize(instance);
+                setBufSize(instance.properties());
 #if !SILVERLIGHT
                 Network.setBlock(_fd, false);
                 if(AssemblyUtil.osx_)
                 {
                     //
                     // On Windows, we delay the join for the mcast group after the connection
-                    // establishment succeeds. This is necessary for older Windows versions 
+                    // establishment succeeds. This is necessary for older Windows versions
                     // where joining the group fails if the socket isn't bound. See ICE-5113.
                     //
                     if(Network.isMulticast((IPEndPoint)_addr))
@@ -810,13 +827,12 @@ namespace IceInternal
         //
         // Only for use by UdpEndpoint.
         //
-        internal UdpTransceiver(Instance instance, string host, int port, string mcastInterface, bool connect)
+        internal UdpTransceiver(ProtocolInstance instance, string host, int port, string mcastInterface, bool connect)
         {
-            _traceLevels = instance.traceLevels();
-            _logger = instance.initializationData().logger;
+            _instance = instance;
             _state = connect ? StateNeedConnect : StateNotConnected;
             _incoming = true;
-            
+
             try
             {
                 _addr = Network.getAddressForServer(host, port, instance.protocolSupport(), instance.preferIPv6());
@@ -825,23 +841,24 @@ namespace IceInternal
                 _readEventArgs = new SocketAsyncEventArgs();
                 _readEventArgs.RemoteEndPoint = _addr;
                 _readEventArgs.Completed += new EventHandler<SocketAsyncEventArgs>(ioCompleted);
-                
+
                 _writeEventArgs = new SocketAsyncEventArgs();
                 _writeEventArgs.RemoteEndPoint = _addr;
                 _writeEventArgs.Completed += new EventHandler<SocketAsyncEventArgs>(ioCompleted);
 #endif
 
                 _fd = Network.createServerSocket(true, _addr.AddressFamily, instance.protocolSupport());
-                setBufSize(instance);
+                setBufSize(instance.properties());
 #if !SILVERLIGHT
                 Network.setBlock(_fd, false);
 #endif
-                if(_traceLevels.network >= 2)
+                if(_instance.traceLevel() >= 2)
                 {
-                    string s = "attempting to bind to udp socket " + Network.addrToString(_addr);
-                    _logger.trace(_traceLevels.networkCat, s);
+                    string s = "attempting to bind to " + instance.protocol() + " socket " +
+                        Network.addrToString(_addr);
+                    _instance.logger().trace(_instance.traceCategory(), s);
                 }
-                
+
 #if !SILVERLIGHT
                 if(Network.isMulticast((IPEndPoint)_addr))
                 {
@@ -852,7 +869,7 @@ namespace IceInternal
                         //
                         // Windows does not allow binding to the mcast address itself
                         // so we bind to INADDR_ANY (0.0.0.0) instead. As a result,
-                        // bi-directional connection won't work because the source 
+                        // bi-directional connection won't work because the source
                         // address won't the multicast address and the client will
                         // therefore reject the datagram.
                         //
@@ -877,13 +894,12 @@ namespace IceInternal
                     if(AssemblyUtil.platform_ != AssemblyUtil.Platform.Windows)
                     {
                         //
-                        // Enable SO_REUSEADDR on Unix platforms to allow
-                        // re-using the socket even if it's in the TIME_WAIT
-                        // state. On Windows, this doesn't appear to be
-                        // necessary and enabling SO_REUSEADDR would actually
-                        // not be a good thing since it allows a second
-                        // process to bind to an address even it's already
-                        // bound by another process.
+                        // Enable SO_REUSEADDR on Unix platforms to allow re-using
+                        // the socket even if it's in the TIME_WAIT state. On
+                        // Windows, this doesn't appear to be necessary and
+                        // enabling SO_REUSEADDR would actually not be a good
+                        // thing since it allows a second process to bind to an
+                        // address even it's already bound by another process.
                         //
                         // TODO: using SO_EXCLUSIVEADDRUSE on Windows would
                         // probably be better but it's only supported by recent
@@ -894,18 +910,18 @@ namespace IceInternal
                     _addr = Network.doBind(_fd, _addr);
                 }
 #endif
-                if(_traceLevels.network >= 1)
+                if(_instance.traceLevel() >= 1)
                 {
-                    StringBuilder s = new StringBuilder("starting to receive udp packets\n");
+                    StringBuilder s = new StringBuilder("starting to receive " + instance.protocol() + " packets\n");
                     s.Append(ToString());
                     List<string> interfaces = Network.getHostsForEndpointExpand(
-                        Network.endpointAddressToString(_addr),  instance.protocolSupport(), true);
+                        Network.endpointAddressToString(_addr), instance.protocolSupport(), true);
                     if(interfaces.Count != 0)
                     {
                         s.Append("\nlocal interfaces: ");
                         s.Append(String.Join(", ", interfaces.ToArray()));
                     }
-                    _logger.trace(_traceLevels.networkCat, s.ToString());
+                    _instance.logger().trace(_instance.traceCategory(), s.ToString());
                 }
             }
             catch(Ice.LocalException)
@@ -915,7 +931,7 @@ namespace IceInternal
             }
         }
 
-        private void setBufSize(Instance instance)
+        private void setBufSize(Ice.Properties properties)
         {
             Debug.Assert(_fd != null);
 
@@ -942,11 +958,11 @@ namespace IceInternal
                 //
                 // Get property for buffer size and check for sanity.
                 //
-                int sizeRequested =
-                    instance.initializationData().properties.getPropertyAsIntWithDefault(prop, dfltSize);
+                int sizeRequested = properties.getPropertyAsIntWithDefault(prop, dfltSize);
                 if(sizeRequested < (_udpOverhead + IceInternal.Protocol.headerSize))
                 {
-                    _logger.warning("Invalid " + prop + " value of " + sizeRequested + " adjusted to " + dfltSize);
+                    _instance.logger().warning("Invalid " + prop + " value of " + sizeRequested + " adjusted to " +
+                                               dfltSize);
                     sizeRequested = dfltSize;
                 }
 
@@ -976,8 +992,8 @@ namespace IceInternal
                     //
                     if(sizeSet < sizeRequested)
                     {
-                        _logger.warning("UDP " + direction + " buffer size: requested size of " + sizeRequested +
-                                        " adjusted to " + sizeSet);
+                        _instance.logger().warning("UDP " + direction + " buffer size: requested size of " +
+                                                   sizeRequested + " adjusted to " + sizeSet);
                     }
                 }
             }
@@ -1020,8 +1036,7 @@ namespace IceInternal
         }
 #endif
 
-        private TraceLevels _traceLevels;
-        private Ice.Logger _logger;
+        private ProtocolInstance _instance;
         private int _state;
         private bool _incoming;
         private int _rcvSize;
diff --git a/cs/src/IceSSL/AcceptorI.cs b/cs/src/IceSSL/AcceptorI.cs
index 273925131c1..2e89e913147 100644
--- a/cs/src/IceSSL/AcceptorI.cs
+++ b/cs/src/IceSSL/AcceptorI.cs
@@ -23,14 +23,14 @@ namespace IceSSL
     {
         public void close()
         {
-            if(_instance.networkTraceLevel() >= 1)
+            if(_instance.traceLevel() >= 1)
             {
-                string s = "stopping to accept ssl connections at " + ToString();
-                _logger.trace(_instance.networkTraceCategory(), s);
+                string s = "stopping to accept " + protocol() + " connections at " + ToString();
+                _instance.logger().trace(_instance.traceCategory(), s);
             }
-            
+
             Debug.Assert(_acceptFd == null);
-            
+
             try
             {
                 _fd.Close();
@@ -46,20 +46,20 @@ namespace IceSSL
         {
             IceInternal.Network.doListen(_fd, _backlog);
 
-            if(_instance.networkTraceLevel() >= 1)
+            if(_instance.traceLevel() >= 1)
             {
-                StringBuilder s = new StringBuilder("listening for ssl connections at ");
+                StringBuilder s = new StringBuilder("listening for " + protocol() + " connections at ");
                 s.Append(ToString());
 
-                List<string> interfaces = 
-                    IceInternal.Network.getHostsForEndpointExpand(_addr.Address.ToString(), 
+                List<string> interfaces =
+                    IceInternal.Network.getHostsForEndpointExpand(_addr.Address.ToString(),
                                                                   _instance.protocolSupport(), true);
                 if(interfaces.Count != 0)
                 {
                     s.Append("\nlocal interfaces: ");
                     s.Append(String.Join(", ", interfaces.ToArray()));
                 }
-                _logger.trace(_instance.networkTraceCategory(), s.ToString());
+                _instance.logger().trace(_instance.traceCategory(), s.ToString());
             }
         }
 
@@ -117,12 +117,13 @@ namespace IceSSL
             }
 
             IceInternal.Network.setBlock(_acceptFd, true); // SSL requires a blocking socket.
-            IceInternal.Network.setTcpBufSize(_acceptFd, _instance.communicator().getProperties(), _logger);
+            IceInternal.Network.setTcpBufSize(_acceptFd, _instance.properties(), _instance.logger());
 
-            if(_instance.networkTraceLevel() >= 1)
+            if(_instance.traceLevel() >= 1)
             {
-                string s = "attempting to accept ssl connection\n" + IceInternal.Network.fdToString(_acceptFd);
-                _logger.trace(_instance.networkTraceCategory(), s);
+                string s = "attempting to accept " + protocol() + " connection\n" +
+                    IceInternal.Network.fdToString(_acceptFd);
+                _instance.logger().trace(_instance.traceCategory(), s);
             }
 
             Socket acceptFd = _acceptFd;
@@ -131,6 +132,11 @@ namespace IceSSL
             return new TransceiverI(_instance, acceptFd, "", true, true, _adapterName, null, null);
         }
 
+        public string protocol()
+        {
+            return _instance.protocol();
+        }
+
         public override string ToString()
         {
             return IceInternal.Network.addrToString(_addr);
@@ -145,8 +151,7 @@ namespace IceSSL
         {
             _instance = instance;
             _adapterName = adapterName;
-            _logger = instance.communicator().getLogger();
-            _backlog = instance.communicator().getProperties().getPropertyAsIntWithDefault("Ice.TCP.Backlog", 511);
+            _backlog = instance.properties().getPropertyAsIntWithDefault("Ice.TCP.Backlog", 511);
 
             //
             // .NET requires that a certificate be supplied.
@@ -162,10 +167,11 @@ namespace IceSSL
             try
             {
                 int protocol = instance.protocolSupport();
-                _addr = (IPEndPoint)IceInternal.Network.getAddressForServer(host, port, protocol, instance.preferIPv6());
+                _addr = IceInternal.Network.getAddressForServer(host, port, protocol, instance.preferIPv6()) as
+                    IPEndPoint;
                 _fd = IceInternal.Network.createServerSocket(false, _addr.AddressFamily, protocol);
                 IceInternal.Network.setBlock(_fd, false);
-                IceInternal.Network.setTcpBufSize(_fd, _instance.communicator().getProperties(), _logger);
+                IceInternal.Network.setTcpBufSize(_fd, _instance.properties(), _instance.logger());
                 if(IceInternal.AssemblyUtil.platform_ != IceInternal.AssemblyUtil.Platform.Windows)
                 {
                     //
@@ -183,10 +189,11 @@ namespace IceSSL
                     //
                     IceInternal.Network.setReuseAddress(_fd, true);
                 }
-                if(_instance.networkTraceLevel() >= 2)
+                if(_instance.traceLevel() >= 2)
                 {
-                    string s = "attempting to bind to ssl socket " + IceInternal.Network.addrToString(_addr);
-                    _logger.trace(_instance.networkTraceCategory(), s);
+                    string s = "attempting to bind to " + protocol() + " socket " +
+                        IceInternal.Network.addrToString(_addr);
+                    _instance.logger().trace(_instance.traceCategory(), s);
                 }
                 _addr = IceInternal.Network.doBind(_fd, _addr);
             }
@@ -199,7 +206,6 @@ namespace IceSSL
 
         private Instance _instance;
         private string _adapterName;
-        private Ice.Logger _logger;
         private Socket _fd;
         private Socket _acceptFd;
         private System.Exception _acceptError;
diff --git a/cs/src/IceSSL/ConnectorI.cs b/cs/src/IceSSL/ConnectorI.cs
index 9aeeb0ae3e0..d903bf712c8 100644
--- a/cs/src/IceSSL/ConnectorI.cs
+++ b/cs/src/IceSSL/ConnectorI.cs
@@ -17,8 +17,6 @@ namespace IceSSL
 
     sealed class ConnectorI : IceInternal.Connector
     {
-        internal const short TYPE = 2;
-
         public IceInternal.Transceiver connect()
         {
             //
@@ -31,10 +29,10 @@ namespace IceSSL
                 throw ex;
             }
 
-            if(_instance.networkTraceLevel() >= 2)
+            if(_instance.traceLevel() >= 2)
             {
-                string s = "trying to establish ssl connection to " + ToString();
-                _logger.trace(_instance.networkTraceCategory(), s);
+                string s = "trying to establish " + _instance.protocol() + " connection to " + ToString();
+                _instance.logger().trace(_instance.traceCategory(), s);
             }
 
             try
@@ -49,7 +47,7 @@ namespace IceSSL
                 //
                 if(_addr.AddressFamily != AddressFamily.InterNetworkV6 || !IceInternal.AssemblyUtil.xp_)
                 {
-                    IceInternal.Network.setTcpBufSize(fd, _instance.communicator().getProperties(), _logger);
+                    IceInternal.Network.setTcpBufSize(fd, _instance.properties(), _instance.logger());
                 }
 
                 //
@@ -59,10 +57,11 @@ namespace IceSSL
             }
             catch(Ice.LocalException ex)
             {
-                if(_instance.networkTraceLevel() >= 2)
+                if(_instance.traceLevel() >= 2)
                 {
-                    string s = "failed to establish ssl connection to " + ToString() + "\n" + ex;
-                    _logger.trace(_instance.networkTraceCategory(), s);
+                    string s = "failed to establish " + _instance.protocol() + " connection to " + ToString() + "\n" +
+                        ex;
+                    _instance.logger().trace(_instance.traceCategory(), s);
                 }
                 throw;
             }
@@ -70,20 +69,20 @@ namespace IceSSL
 
         public short type()
         {
-            return TYPE;
+            return _instance.type();
         }
 
         //
         // Only for use by EndpointI.
         //
-        internal ConnectorI(Instance instance, string host, EndPoint addr, IceInternal.NetworkProxy proxy, int timeout, 
+        internal ConnectorI(Instance instance, string host, EndPoint addr, IceInternal.NetworkProxy proxy, int timeout,
                             string conId)
         {
             _instance = instance;
             _host = host;
-            _logger = instance.communicator().getLogger();
+            _instance.logger() = instance.communicator().getLogger();
             _addr = (IPEndPoint)addr;
-            _proxy = proxy; 
+            _proxy = proxy;
             _timeout = timeout;
             _connectionId = conId;
 
@@ -130,7 +129,6 @@ namespace IceSSL
         }
 
         private Instance _instance;
-        private Ice.Logger _logger;
         private string _host;
         private IPEndPoint _addr;
         private IceInternal.NetworkProxy _proxy;
diff --git a/cs/src/IceSSL/EndpointI.cs b/cs/src/IceSSL/EndpointI.cs
index fe1bbbe321f..cb39879cacc 100644
--- a/cs/src/IceSSL/EndpointI.cs
+++ b/cs/src/IceSSL/EndpointI.cs
@@ -14,281 +14,66 @@ namespace IceSSL
     using System.Collections.Generic;
     using System.Net;
     using System.Globalization;
-        
-    sealed class EndpointI : IceInternal.EndpointI
+
+    sealed class EndpointI : IceInternal.IPEndpointI
     {
-        internal EndpointI(Instance instance, string ho, int po, int ti, string conId, bool co) : base(conId)
+        internal EndpointI(Instance instance, string ho, int po, int ti, string conId, bool co) :
+            base(instance, ho, po, conId)
         {
             _instance = instance;
-            _host = ho;
-            _port = po;
             _timeout = ti;
-            connectionId_ = conId;
             _compress = co;
-            calcHashValue();
         }
 
-        internal EndpointI(Instance instance, string str, bool oaEndpoint) : base("")
+        internal EndpointI(Instance instance)
         {
+            base(instance);
             _instance = instance;
-            _host = null;
-            _port = 0;
             _timeout = -1;
             _compress = false;
-
-            char[] separators = { ' ', '\t', '\n', '\r' };
-            string[] arr = str.Split(separators);
-
-            int i = 0;
-            while(i < arr.Length)
-            {
-                if(arr[i].Length == 0)
-                {
-                    i++;
-                    continue;
-                }
-
-                string option = arr[i++];
-                if(option.Length != 2 || option[0] != '-')
-                {
-                    Ice.EndpointParseException e = new Ice.EndpointParseException();
-                    e.str = "expected an endpoint option but found `" + option + "' in endpoint `ssl " + str + "'";
-                    throw e;
-                }
-
-                string argument = null;
-                if(i < arr.Length && arr[i][0] != '-')
-                {
-                    argument = arr[i++];
-                    if(argument[0] == '\"' && argument[argument.Length - 1] == '\"')
-                    {
-                        argument = argument.Substring(1, argument.Length - 2);
-                    }
-                }
-
-                switch(option[1])
-                {
-                    case 'h':
-                    {
-                        if(argument == null)
-                        {
-                            Ice.EndpointParseException e = new Ice.EndpointParseException();
-                            e.str = "no argument provided for -h option in endpoint `ssl " + str + "'";
-                            throw e;
-                        }
-
-                        _host = argument;
-                        break;
-                    }
-
-                    case 'p':
-                    {
-                        if(argument == null)
-                        {
-                            Ice.EndpointParseException e = new Ice.EndpointParseException();
-                            e.str = "no argument provided for -p option in endpoint `ssl " + str + "'";
-                            throw e;
-                        }
-
-                        try
-                        {
-                            _port = System.Int32.Parse(argument, CultureInfo.InvariantCulture);
-                        }
-                        catch(System.FormatException ex)
-                        {
-                            Ice.EndpointParseException e = new Ice.EndpointParseException(ex);
-                            e.str = "invalid port value `" + argument + "' in endpoint `ssl " + str + "'";
-                            throw e;
-                        }
-
-                        if(_port < 0 || _port > 65535)
-                        {
-                            Ice.EndpointParseException e = new Ice.EndpointParseException();
-                            e.str = "port value `" + argument + "' out of range in endpoint `ssl " + str + "'";
-                            throw e;
-                        }
-
-                        break;
-                    }
-
-                    case 't':
-                    {
-                        if(argument == null)
-                        {
-                            Ice.EndpointParseException e = new Ice.EndpointParseException();
-                            e.str = "no argument provided for -t option in endpoint `ssl " + str + "'";
-                            throw e;
-                        }
-
-                        try
-                        {
-                            _timeout = System.Int32.Parse(argument, CultureInfo.InvariantCulture);
-                        }
-                        catch(System.FormatException ex)
-                        {
-                            Ice.EndpointParseException e = new Ice.EndpointParseException(ex);
-                            e.str = "invalid timeout value `" + argument + "' in endpoint `ssl " + str + "'";
-                            throw e;
-                        }
-
-                        break;
-                    }
-
-                    case 'z':
-                    {
-                        if(argument != null)
-                        {
-                            Ice.EndpointParseException e = new Ice.EndpointParseException();
-                            e.str = "unexpected argument `" + argument + "' provided for -z option in `ssl " + str +
-                                    "'";
-                            throw e;
-                        }
-
-                        _compress = true;
-                        break;
-                    }
-
-                    default:
-                    {
-                        throw new Ice.EndpointParseException("unknown option `" + option + "' in endpoint `ssl " + str + "'");
-                    }
-                }
-            }
-
-            if(_host == null)
-            {
-                _host = _instance.defaultHost();
-            }
-            else if(_host.Equals("*"))
-            {
-                if(oaEndpoint)
-                {
-                    _host = null;
-                }
-                else
-                {
-                    throw new Ice.EndpointParseException("`-h *' not valid for proxy endpoint `ssl " + str + "'");
-                }
-            }
-
-            if(_host == null)
-            {
-                _host = "";
-            }
-
-            calcHashValue();
         }
 
         internal EndpointI(Instance instance, IceInternal.BasicStream s)
         {
+            base(instance, s);
             _instance = instance;
-            s.startReadEncaps();
-            _host = s.readString();
-            _port = s.readInt();
             _timeout = s.readInt();
             _compress = s.readBool();
-            s.endReadEncaps();
-            calcHashValue();
-        }
-
-        //
-        // Marshal the endpoint.
-        //
-        public override void streamWrite(IceInternal.BasicStream s)
-        {
-            s.writeShort(EndpointType.value);
-            s.startWriteEncaps();
-            s.writeString(_host);
-            s.writeInt(_port);
-            s.writeInt(_timeout);
-            s.writeBool(_compress);
-            s.endWriteEncaps();
         }
 
-        //
-        // Convert the endpoint to its string form.
-        //
-        public override string ice_toString_()
-        {
-            //
-            // WARNING: Certain features, such as proxy validation in Glacier2,
-            // depend on the format of proxy strings. Changes to toString() and
-            // methods called to generate parts of the reference string could break
-            // these features. Please review for all features that depend on the
-            // format of proxyToString() before changing this and related code.
-            //
-            string s = "ssl";
-
-            if(_host != null && _host.Length != 0)
-            {
-                s += " -h ";
-                bool addQuote = _host.IndexOf(':') != -1;
-                if(addQuote)
-                {
-                    s += "\"";
-                }
-                s += _host;
-                if(addQuote)
-                {
-                    s += "\"";
-                }
-            }
-            s += " -p " + _port;
-            if(_timeout != -1)
-            {
-                s += " -t " + _timeout;
-            }
-            if(_compress)
-            {
-                s += " -z";
-            }
-            return s;
-        }
-        
         private sealed class InfoI : IceSSL.EndpointInfo
         {
-            public InfoI(int to, bool comp, string h, int p) : base(to, comp, h, p)
+            public InfoI(EndpointI e)
             {
+                _endpoint = e;
             }
 
             override public short type()
             {
-                return EndpointType.value;
+                return _endpoint.type();
             }
-            
+
             override public bool datagram()
             {
-                return false;
+                return _endpoint.datagram();
             }
-                
+
             override public bool secure()
             {
-                return true;
+                return _endpoint.secure();
             }
-        };
 
-        //
-        // Return the endpoint information.
-        //
-        public override Ice.EndpointInfo getInfo()
-        {
-            return new InfoI(_timeout, _compress, _host, _port);
+            private EndpointI _endpoint;
         }
 
         //
-        // Return the endpoint type.
-        //
-        public override short type()
-        {
-            return EndpointType.value;
-        }
-
-        //
-        // Return the protocol name;
+        // Return the endpoint information.
         //
-        public override string protocol()
+        public override Ice.EndpointInfo getInfo()
         {
-            return "ssl";
+            InfoI info = new InfoI(this);
+            fillEndpointInfo(info);
+            return info;
         }
 
         //
@@ -313,22 +98,7 @@ namespace IceSSL
             }
             else
             {
-                return new EndpointI(_instance, _host, _port, timeout, connectionId_, _compress);
-            }
-        }
-
-        //
-        // Return a new endpoint with a different connection id.
-        //
-        public override IceInternal.EndpointI connectionId(string connectionId)
-        {
-            if(connectionId == connectionId_)
-            {
-                return this;
-            }
-            else
-            {
-                return new EndpointI(_instance, _host, _port, _timeout, connectionId, _compress);
+                return new EndpointI(_instance, host_, port_, timeout, connectionId_, _compress);
             }
         }
 
@@ -354,7 +124,7 @@ namespace IceSSL
             }
             else
             {
-                return new EndpointI(_instance, _host, _port, _timeout, connectionId_, compress);
+                return new EndpointI(_instance, host_, port_, _timeout, connectionId_, compress);
             }
         }
 
@@ -388,21 +158,6 @@ namespace IceSSL
         }
 
         //
-        // Return connectors for this endpoint, or empty list if no connector
-        // is available.
-        //
-        public override List<IceInternal.Connector> connectors(Ice.EndpointSelectionType selType)
-        {
-            return _instance.endpointHostResolver().resolve(_host, _port, selType, this);
-        }
-
-        public override void connectors_async(Ice.EndpointSelectionType selType,
-                                              IceInternal.EndpointI_connectors callback)
-        {
-            _instance.endpointHostResolver().resolve(_host, _port, selType, this, callback);
-        }
-
-        //
         // Return an acceptor for this endpoint, or null if no acceptor
         // is available. In case an acceptor is created, this operation
         // also returns a new "effective" endpoint, which might differ
@@ -411,61 +166,33 @@ namespace IceSSL
         //
         public override IceInternal.Acceptor acceptor(ref IceInternal.EndpointI endpoint, string adapterName)
         {
-            AcceptorI p = new AcceptorI(_instance, adapterName, _host, _port);
-            endpoint = new EndpointI(_instance, _host, p.effectivePort(), _timeout, connectionId_, _compress);
+            AcceptorI p = new AcceptorI(_instance, adapterName, host_, port_);
+            endpoint = new EndpointI(_instance, host_, p.effectivePort(), _timeout, connectionId_, _compress);
             return p;
         }
 
-        //
-        // Expand endpoint out in to separate endpoints for each local
-        // host if listening on INADDR_ANY.
-        //
-        public override List<IceInternal.EndpointI> expand()
+        public override string options()
         {
-            List<IceInternal.EndpointI> endps = new List<IceInternal.EndpointI>();
-            List<string> hosts = 
-                IceInternal.Network.getHostsForEndpointExpand(_host, _instance.protocolSupport(), false);
-            if(hosts == null || hosts.Count == 0)
-            {
-                endps.Add(this);
-            }
-            else
-            {
-                foreach(string h in hosts)
-                {
-                    endps.Add(new EndpointI(_instance, h, _port, _timeout, connectionId_, _compress));
-                }
-            }
-            return endps;
-        }
+            //
+            // WARNING: Certain features, such as proxy validation in Glacier2,
+            // depend on the format of proxy strings. Changes to toString() and
+            // methods called to generate parts of the reference string could break
+            // these features. Please review for all features that depend on the
+            // format of proxyToString() before changing this and related code.
+            //
+            string s = base.options();
 
-        //
-        // Check whether the endpoint is equivalent to another one.
-        //
-        public override bool equivalent(IceInternal.EndpointI endpoint)
-        {
-            if(!(endpoint is EndpointI))
+            if(_timeout != -1)
             {
-                return false;
+                s += " -t " + _timeout;
             }
 
-            EndpointI sslEndpointI = (EndpointI)endpoint;
-            return sslEndpointI._host.Equals(_host) && sslEndpointI._port == _port;
-        }
-
-        public override List<IceInternal.Connector> connectors(List<EndPoint> addresses, IceInternal.NetworkProxy proxy)
-        {
-            List<IceInternal.Connector> connectors = new List<IceInternal.Connector>();
-            foreach(EndPoint addr in addresses)
+            if(_compress)
             {
-                connectors.Add(new ConnectorI(_instance, _host, addr, proxy, _timeout, connectionId_));
+                s += " -z";
             }
-            return connectors;
-        }
 
-        public override int GetHashCode()
-        {
-            return _hashCode;
+            return s;
         }
 
         //
@@ -477,74 +204,124 @@ namespace IceSSL
             {
                 return type() < obj.type() ? -1 : 1;
             }
-            
+
             EndpointI p = (EndpointI)obj;
             if(this == p)
             {
                 return 0;
             }
-            else
-            {
-                int r = base.CompareTo(p);
-                if(r != 0)
-                {
-                    return r;
-                }
-            }
 
-            if(_port < p._port)
+            if(_timeout < p._timeout)
             {
                 return -1;
             }
-            else if(p._port < _port)
+            else if(p._timeout < _timeout)
             {
                 return 1;
             }
 
-            if(_timeout < p._timeout)
+            if(!_compress && p._compress)
             {
                 return -1;
             }
-            else if(p._timeout < _timeout)
+            else if(!p._compress && _compress)
             {
                 return 1;
             }
 
-            if(!connectionId_.Equals(p.connectionId_))
+            return base.CompareTo(p);
+        }
+
+        protected override void streamWriteImpl(IceInternal.BasicStream s)
+        {
+            base.streamWriteImpl(s);
+            s.writeInt(_timeout);
+            s.writeBool(_compress);
+        }
+
+        protected override void hashInit(ref int h)
+        {
+            base.hashInit(ref h);
+            IceInternal.HashUtil.hashAdd(ref h, _timeout);
+            IceInternal.HashUtil.hashAdd(ref h, _compress);
+        }
+
+        protected override void fillEndpointInfo(Ice.IPEndpointInfo info)
+        {
+            base.fillEndpointInfo(info);
+            if(info is IceSSL.EndpointInfo)
             {
-                return string.Compare(connectionId_, p.connectionId_, StringComparison.Ordinal);
+                IceSSL.EndpointInfo sslInfo = (IceSSL.EndpointInfo)info;
+                sslInfo.timeout = _timeout;
+                sslInfo.compress = _compress;
             }
+        }
 
-            if(!_compress && p._compress)
+        protected override bool checkOption(string option, string argument, string endpoint)
+        {
+            if(base.checkOption(option, argument, endpoint))
             {
-                return -1;
+                return true;
             }
-            else if(!p._compress && _compress)
+
+            switch(option[1])
             {
-                return 1;
+            case 't':
+            {
+                if(argument == null)
+                {
+                    Ice.EndpointParseException e = new Ice.EndpointParseException();
+                    e.str = "no argument provided for -t option in endpoint " + endpoint;
+                    throw e;
+                }
+
+                try
+                {
+                    _timeout = System.Int32.Parse(argument, CultureInfo.InvariantCulture);
+                }
+                catch(System.FormatException ex)
+                {
+                    Ice.EndpointParseException e = new Ice.EndpointParseException(ex);
+                    e.str = "invalid timeout value `" + argument + "' in endpoint " + endpoint;
+                    throw e;
+                }
+
+                return true;
+            }
+
+            case 'z':
+            {
+                if(argument != null)
+                {
+                    Ice.EndpointParseException e = new Ice.EndpointParseException();
+                    e.str = "unexpected argument `" + argument + "' provided for -z option in " + endpoint;
+                    throw e;
+                }
+
+                _compress = true;
+                return true;
             }
 
-            return string.Compare(_host, p._host, StringComparison.Ordinal);
+            default:
+            {
+                return false;
+            }
+            }
         }
 
-        private void calcHashValue()
+        protected override IceInternal.Connector createConnector(EndPoint addr, IceInternal.NetworkProxy proxy)
         {
-            int h = 5381;
-            IceInternal.HashUtil.hashAdd(ref h, EndpointType.value);
-            IceInternal.HashUtil.hashAdd(ref h, _host);
-            IceInternal.HashUtil.hashAdd(ref h, _port);
-            IceInternal.HashUtil.hashAdd(ref h, _timeout);
-            IceInternal.HashUtil.hashAdd(ref h, connectionId_);
-            IceInternal.HashUtil.hashAdd(ref h, _compress);
-            _hashCode = h;
+            return new ConnectorI(_instance, host_, addr, proxy, _timeout, connectionId_);
+        }
+
+        protected override IceInternal.IPEndpointI createEndpoint(string host, int port, string connectionId)
+        {
+            return new EndpointI(_instance, host, port, _timeout, connectionId, _compress);
         }
 
         private Instance _instance;
-        private string _host;
-        private int _port;
         private int _timeout;
         private bool _compress;
-        private int _hashCode;
     }
 
     internal sealed class EndpointFactoryI : IceInternal.EndpointFactory
@@ -556,17 +333,19 @@ namespace IceSSL
 
         public short type()
         {
-            return EndpointType.value;
+            return _instance.type();
         }
 
         public string protocol()
         {
-            return "ssl";
+            return _instance.protocol();
         }
 
-        public IceInternal.EndpointI create(string str, bool oaEndpoint)
+        public IceInternal.EndpointI create(List<string> args, bool oaEndpoint)
         {
-            return new EndpointI(_instance, str, oaEndpoint);
+            IceInternal.IPEndpointI endpt = new EndpointI(_instance);
+            endpt.initWithOptions(args, oaEndpoint);
+            return endpt;
         }
 
         public IceInternal.EndpointI read(IceInternal.BasicStream s)
@@ -579,6 +358,11 @@ namespace IceSSL
             _instance = null;
         }
 
+        public IceInternal.EndpointFactory clone(IceInternal.ProtocolInstance instance)
+        {
+            return new EndpointFactoryI(new Instance(_instance.sharedInstance(), instance.type(), instance.protocol()));
+        }
+
         private Instance _instance;
     }
 }
diff --git a/cs/src/IceSSL/Instance.cs b/cs/src/IceSSL/Instance.cs
index 3ca13045433..b9c30126f70 100644
--- a/cs/src/IceSSL/Instance.cs
+++ b/cs/src/IceSSL/Instance.cs
@@ -19,24 +19,18 @@ namespace IceSSL
     using System.Security.Cryptography.X509Certificates;
     using System.Text;
     using System.Globalization;
-        
-    internal class Instance
+
+    internal class SharedInstance
     {
-        internal Instance(Ice.Communicator communicator)
+        internal SharedInstance(IceInternal.ProtocolPluginFacade facade)
         {
-            _logger = communicator.getLogger();
-            _facade = IceInternal.Util.getProtocolPluginFacade(communicator);
-            _securityTraceLevel = communicator.getProperties().getPropertyAsIntWithDefault("IceSSL.Trace.Security", 0);
+            _communicator = facade.getCommunicator();
+            _logger = _communicator.getLogger();
+            _facade = facade;
+            _securityTraceLevel = _communicator.getProperties().getPropertyAsIntWithDefault("IceSSL.Trace.Security", 0);
             _securityTraceCategory = "Security";
             _initialized = false;
             _trustManager = new TrustManager(communicator);
-
-            //
-            // Register the endpoint factory. We have to do this now, rather than
-            // in initialize, because the communicator may need to interpret
-            // proxies before the plug-in is fully initialized.
-            //
-            _facade.addEndpointFactory(new EndpointFactoryI(this));
         }
 
         internal void initialize()
@@ -208,7 +202,7 @@ namespace IceSSL
                 _certs = new X509Certificate2Collection();
                 string certFile = properties.getProperty(prefix + "CertFile");
                 string passwordStr = properties.getProperty(prefix + "Password");
-                
+
                 if(certFile.Length > 0)
                 {
                     if(!checkPath(ref certFile))
@@ -318,46 +312,6 @@ namespace IceSSL
             return _facade.getCommunicator();
         }
 
-        internal IceInternal.EndpointHostResolver endpointHostResolver()
-        {
-            return _facade.getEndpointHostResolver();
-        }
-
-        internal int protocolSupport()
-        {
-            return _facade.getProtocolSupport();
-        }
-
-        internal bool preferIPv6()
-        {
-            return _facade.getPreferIPv6();
-        }
-
-        internal IceInternal.NetworkProxy networkProxy()
-        {
-            return _facade.getNetworkProxy();
-        }
-
-        internal Ice.EncodingVersion defaultEncoding()
-        {
-            return _facade.getDefaultEncoding();
-        }
-
-        internal string defaultHost()
-        {
-            return _facade.getDefaultHost();
-        }
-
-        internal int networkTraceLevel()
-        {
-            return _facade.getNetworkTraceLevel();
-        }
-
-        internal string networkTraceCategory()
-        {
-            return _facade.getNetworkTraceCategory();
-        }
-
         internal int securityTraceLevel()
         {
             return _securityTraceLevel;
@@ -405,7 +359,7 @@ namespace IceSSL
             s.Append("\ncipher algorithm = " + stream.CipherAlgorithm + "/" + stream.CipherStrength);
             s.Append("\nkey exchange algorithm = " + stream.KeyExchangeAlgorithm + "/" + stream.KeyExchangeStrength);
             s.Append("\nprotocol = " + stream.SslProtocol);
-            communicator().getLogger().trace(_securityTraceCategory, s.ToString());
+            _logger.trace(_securityTraceCategory, s.ToString());
         }
 
         internal void verifyPeer(NativeConnectionInfo info, System.Net.Sockets.Socket fd, string address)
@@ -633,7 +587,7 @@ namespace IceSSL
 
             if(_verifier != null && !_verifier.verify(info))
             {
-                string msg = (info.incoming ? "incoming" : "outgoing") + 
+                string msg = (info.incoming ? "incoming" : "outgoing") +
                     " connection rejected by certificate verifier\n" + IceInternal.Network.fdToString(fd);
                 if(_securityTraceLevel >= 1)
                 {
@@ -649,7 +603,8 @@ namespace IceSSL
         //
         // Parse a string of the form "location.name" into two parts.
         //
-        internal void parseStore(string prop, string store, ref StoreLocation loc, ref StoreName name, ref string sname)
+        private static void parseStore(string prop, string store, ref StoreLocation loc, ref StoreName name,
+                                       ref string sname)
         {
             int pos = store.IndexOf('.');
             if(pos == -1)
@@ -823,7 +778,7 @@ namespace IceSSL
         // Split strings using a delimiter. Quotes are supported.
         // Returns null for an unmatched quote.
         //
-        private string[] splitString(string str, char delim)
+        private static string[] splitString(string str, char delim)
         {
             ArrayList l = new ArrayList();
             char[] arr = new char[str.Length];
@@ -889,7 +844,7 @@ namespace IceSSL
         private SslProtocols parseProtocols(string property)
         {
             SslProtocols result = SslProtocols.Default;
-            string[] arr = communicator().getProperties().getPropertyAsList(property);
+            string[] arr = _communicator.getProperties().getPropertyAsList(property);
             if(arr.Length > 0)
             {
                 result = 0;
@@ -912,13 +867,13 @@ namespace IceSSL
                             protocol = "Tls";
                             break;
                         }
-                        case "TLS1_1": 
+                        case "TLS1_1":
                         case "TLSV1_1":
                         {
                             protocol = "Tls11";
                             break;
                         }
-                        case "TLS1_2": 
+                        case "TLS1_2":
                         case "TLSV1_2":
                         {
                             protocol = "Tls12";
@@ -946,7 +901,7 @@ namespace IceSSL
             return result;
         }
 
-        private X509Certificate2Collection findCertificates(string prop, string storeSpec, string value)
+        private static X509Certificate2Collection findCertificates(string prop, string storeSpec, string value)
         {
             StoreLocation storeLoc = 0;
             StoreName storeName = 0;
@@ -1159,6 +1114,7 @@ namespace IceSSL
             return (next + len <= data.Length);
         }
 
+        private Ice.Communicator _communicator;
         private Ice.Logger _logger;
         private IceInternal.ProtocolPluginFacade _facade;
         private int _securityTraceLevel;
@@ -1174,4 +1130,60 @@ namespace IceSSL
         private PasswordCallback _passwordCallback;
         private TrustManager _trustManager;
     }
+
+    internal class Instance : IceInternal.ProtocolInstance
+    {
+        internal Instance(SharedInstance sharedInstance, short type, string protocol)
+        {
+            base(sharedInstance.communicator(), type, protocol);
+            _sharedInstance = sharedInstance;
+        }
+
+        internal SharedInstance sharedInstance()
+        {
+            return _sharedInstance;
+        }
+
+        internal int securityTraceLevel()
+        {
+            return _sharedInstance.securityTraceLevel();
+        }
+
+        internal string securityTraceCategory()
+        {
+            return _sharedInstance.securityTraceCategory();
+        }
+
+        internal bool initialized()
+        {
+            return _sharedInstance.initialized();
+        }
+
+        internal X509Certificate2Collection certs()
+        {
+            return _sharedInstance.certs();
+        }
+
+        internal SslProtocols protocols()
+        {
+            return _sharedInstance.protocols();
+        }
+
+        internal int checkCRL()
+        {
+            return _sharedInstance.checkCRL();
+        }
+
+        internal void traceStream(System.Net.Security.SslStream stream, string connInfo)
+        {
+            _sharedInstance.traceStream(stream, connInfo);
+        }
+
+        internal void verifyPeer(NativeConnectionInfo info, System.Net.Sockets.Socket fd, string address)
+        {
+            _sharedInstance.verifyPeer(info, fd, address);
+        }
+
+        private SharedInstance _sharedInstance;
+    }
 }
diff --git a/cs/src/IceSSL/PluginI.cs b/cs/src/IceSSL/PluginI.cs
index d5f212f6b84..7a2fb6a21c7 100644
--- a/cs/src/IceSSL/PluginI.cs
+++ b/cs/src/IceSSL/PluginI.cs
@@ -26,8 +26,7 @@ namespace IceSSL
         /// <returns>The new plug-in. null can be returned to indicate
         /// that a general error occurred. Alternatively, create can throw
         /// PluginInitializationException to provide more detailed information.</returns>
-        public Ice.Plugin
-        create(Ice.Communicator communicator, string name, string[] args)
+        public Ice.Plugin create(Ice.Communicator communicator, string name, string[] args)
         {
             return new PluginI(communicator);
         }
@@ -35,47 +34,55 @@ namespace IceSSL
 
     public sealed class PluginI : Plugin
     {
-        public
-        PluginI(Ice.Communicator communicator)
+        public PluginI(Ice.Communicator communicator)
         {
-            instance_ = new Instance(communicator);
+            IceInternal.ProtocolPluginFacade facade = IceInternal.Util.getProtocolPluginFacade(communicator);
+
+            _sharedInstance = new SharedInstance(facade);
+
+            //
+            // Register the endpoint factory. We have to do this now, rather than
+            // in initialize, because the communicator may need to interpret
+            // proxies before the plug-in is fully initialized.
+            //
+            facade.addEndpointFactory(
+                new EndpointFactoryI(new Instance(_sharedInstance, IceSSL.EndpointType.value, "ssl")));
         }
 
         public override void initialize()
         {
-            instance_.initialize();
+            _sharedInstance.initialize();
         }
 
-        public override void
-        destroy()
+        public override void destroy()
         {
         }
 
         public override void setCertificates(X509Certificate2Collection certs)
         {
-            instance_.setCertificates(certs);
+            _sharedInstance.setCertificates(certs);
         }
 
         public override void setCertificateVerifier(CertificateVerifier verifier)
         {
-            instance_.setCertificateVerifier(verifier);
+            _sharedInstance.setCertificateVerifier(verifier);
         }
 
         public override CertificateVerifier getCertificateVerifier()
         {
-            return instance_.getCertificateVerifier();
+            return _sharedInstance.getCertificateVerifier();
         }
 
         public override void setPasswordCallback(PasswordCallback callback)
         {
-            instance_.setPasswordCallback(callback);
+            _sharedInstance.setPasswordCallback(callback);
         }
 
         public override PasswordCallback getPasswordCallback()
         {
-            return instance_.getPasswordCallback();
+            return _sharedInstance.getPasswordCallback();
         }
 
-        private Instance instance_;
+        private SharedInstance _sharedInstance;
     }
 }
diff --git a/cs/src/IceSSL/TransceiverI.cs b/cs/src/IceSSL/TransceiverI.cs
index cd29bfa8bb9..89942b4dccb 100644
--- a/cs/src/IceSSL/TransceiverI.cs
+++ b/cs/src/IceSSL/TransceiverI.cs
@@ -24,7 +24,7 @@ namespace IceSSL
 
     sealed class TransceiverI : IceInternal.Transceiver
     {
-        public int initialize()
+        public int initialize(IceInternal.Buffer readBuffer, IceInternal.Buffer writeBuffer, ref bool hasMoreData)
         {
             try
             {
@@ -34,7 +34,7 @@ namespace IceSSL
                     _state = StateConnectPending;
                     return IceInternal.SocketOperation.Connect;
                 }
-                else if(_state == StateConnectPending)
+                else if(_state <= StateConnectPending)
                 {
                     IceInternal.Network.doFinishConnectAsync(_fd, _writeResult);
                     _writeResult = null;
@@ -43,7 +43,7 @@ namespace IceSSL
                     if(_proxy != null)
                     {
                         _state = StateProxyConnectRequest; // Send proxy connect request
-                        return IceInternal.SocketOperation.Write; 
+                        return IceInternal.SocketOperation.Write;
                     }
 
                     _state = StateAuthenticatePending;
@@ -74,25 +74,32 @@ namespace IceSSL
             }
             catch(Ice.LocalException e)
             {
-                if(_instance.networkTraceLevel() >= 2)
+                if(_instance.traceLevel() >= 2)
                 {
                     System.Text.StringBuilder s = new System.Text.StringBuilder();
-                    s.Append("failed to establish ssl connection\n");
+                    s.Append("failed to establish " + protocol() + " connection\n");
                     s.Append(IceInternal.Network.fdToString(_fd, _proxy, _addr));
                     s.Append("\n");
                     s.Append(e.ToString());
-                    _logger.trace(_instance.networkTraceCategory(), s.ToString());
+                    _instance.logger().trace(_instance.traceCategory(), s.ToString());
                 }
                 throw;
             }
         }
 
+        public int closing(bool initiator, Ice.LocalException ex)
+        {
+            // If we are initiating the connection closure, wait for the peer
+            // to close the TCP/IP connection. Otherwise, close immediately.
+            return initiator ? IceInternal.SocketOperation.Read : IceInternal.SocketOperation.None;
+        }
+
         public void close()
         {
-            if(_state == StateConnected && _instance.networkTraceLevel() >= 1)
+            if(_state == StateConnected && _instance.traceLevel() >= 1)
             {
-                string s = "closing ssl connection\n" + ToString();
-                _logger.trace(_instance.networkTraceCategory(), s);
+                string s = "closing " + protocol() + " connection\n" + ToString();
+                _instance.logger().trace(_instance.traceCategory(), s);
             }
 
             Debug.Assert(_fd != null);
@@ -121,16 +128,22 @@ namespace IceSSL
             }
         }
 
-        public bool write(IceInternal.Buffer buf)
+        public int write(IceInternal.Buffer buf)
         {
             Debug.Assert(_fd != null);
-            return false; // Caller will use async write.
+            //
+            // Force caller to use async write.
+            //
+            return buf.b.hasRemaining() ? IceInternal.SocketOperation.Write : IceInternal.SocketOperation.None;
         }
 
-        public bool read(IceInternal.Buffer buf)
+        public int read(IceInternal.Buffer buf, ref bool hasMoreData)
         {
             Debug.Assert(_fd != null);
-            return false; // Caller will use async read.
+            //
+            // Force caller to use async read.
+            //
+            return buf.b.hasRemaining() ? IceInternal.SocketOperation.Read : IceInternal.SocketOperation.None;
         }
 
         public bool startRead(IceInternal.Buffer buf, IceInternal.AsyncCallback callback, object state)
@@ -210,7 +223,7 @@ namespace IceSSL
 
                 Debug.Assert(ret > 0);
 
-                if(_instance.networkTraceLevel() >= 3)
+                if(_instance.traceLevel() >= 3)
                 {
                     int packetSize = buf.b.remaining();
                     if(_maxReceivePacketSize > 0 && packetSize > _maxReceivePacketSize)
@@ -218,7 +231,7 @@ namespace IceSSL
                         packetSize = _maxReceivePacketSize;
                     }
                     string s = "received " + ret + " of " + packetSize + " bytes via ssl\n" + ToString();
-                    _logger.trace(_instance.networkTraceCategory(), s);
+                    _instance.logger().trace(_instance.traceCategory(), s);
                 }
 
                 buf.b.position(buf.b.position() + ret);
@@ -254,11 +267,11 @@ namespace IceSSL
             }
         }
 
-        public bool startWrite(IceInternal.Buffer buf, IceInternal.AsyncCallback callback, object state, 
+        public bool startWrite(IceInternal.Buffer buf, IceInternal.AsyncCallback callback, object state,
                                out bool completed)
         {
             Debug.Assert(_fd != null);
-            
+
             if(_state < StateConnected)
             {
                 completed = false;
@@ -300,12 +313,12 @@ namespace IceSSL
                 _writeCallback = callback;
                 if(_stream != null)
                 {
-                    _writeResult = _stream.BeginWrite(buf.b.rawBytes(), buf.b.position(), packetSize, writeCompleted, 
+                    _writeResult = _stream.BeginWrite(buf.b.rawBytes(), buf.b.position(), packetSize, writeCompleted,
                                                       state);
                 }
                 else
                 {
-                    _writeResult = _fd.BeginSend(buf.b.rawBytes(), buf.b.position(), packetSize, SocketFlags.None, 
+                    _writeResult = _fd.BeginSend(buf.b.rawBytes(), buf.b.position(), packetSize, SocketFlags.None,
                                                  writeCompleted, state);
                 }
                 completed = packetSize == buf.b.remaining();
@@ -346,9 +359,9 @@ namespace IceSSL
                     buf.b.position(buf.size()); // Assume all the data was sent for at-most-once semantics.
                 }
                 _writeResult = null;
-                return; 
+                return;
             }
-            
+
             if(_state < StateConnected && _state != StateProxyConnectRequest)
             {
                 return;
@@ -374,10 +387,11 @@ namespace IceSSL
                     packetSize = _maxSendPacketSize;
                 }
 
-                if(_instance.networkTraceLevel() >= 3)
+                if(_instance.traceLevel() >= 3)
                 {
-                    string s = "sent " + packetSize + " of " + packetSize + " bytes via ssl\n" + ToString();
-                    _logger.trace(_instance.networkTraceCategory(), s);
+                    string s = "sent " + packetSize + " of " + packetSize + " bytes via " + protocol() + "\n" +
+                        ToString();
+                    _instance.logger().trace(_instance.traceCategory(), s);
                 }
 
                 buf.b.position(buf.b.position() + packetSize);
@@ -413,9 +427,9 @@ namespace IceSSL
             }
         }
 
-        public string type()
+        public string protocol()
         {
-            return "ssl";
+            return _instance.protocol();
         }
 
         public Ice.ConnectionInfo getInfo()
@@ -450,7 +464,6 @@ namespace IceSSL
             _addr = addr;
             _proxy = proxy;
             _stream = null;
-            _logger = instance.communicator().getLogger();
             _desc = connected ? IceInternal.Network.fdToString(_fd, _proxy, _addr) : "<not connected>";
             _state = connected ? StateNeedAuthenticate : StateNeedConnect;
 
@@ -471,8 +484,7 @@ namespace IceSSL
                 //
                 // Determine whether a certificate is required from the peer.
                 //
-                _verifyPeer =
-                    _instance.communicator().getProperties().getPropertyAsIntWithDefault("IceSSL.VerifyPeer", 2);
+                _verifyPeer = _instance.properties().getPropertyAsIntWithDefault("IceSSL.VerifyPeer", 2);
             }
             else
             {
@@ -480,7 +492,6 @@ namespace IceSSL
             }
         }
 
-
         private NativeConnectionInfo getNativeConnectionInfo()
         {
             IceSSL.NativeConnectionInfo info = new IceSSL.NativeConnectionInfo();
@@ -557,7 +568,7 @@ namespace IceSSL
                     }
 
                     _writeResult = _stream.BeginAuthenticateAsServer(cert, _verifyPeer > 1, _instance.protocols(),
-                                                                     _instance.checkCRL() > 0, 
+                                                                     _instance.checkCRL() > 0,
                                                                      delegate(IAsyncResult result)
                                                                      {
                                                                          if(!result.CompletedSynchronously)
@@ -611,18 +622,18 @@ namespace IceSSL
 
                 _instance.verifyPeer(getNativeConnectionInfo(), _fd, _host);
 
-                if(_instance.networkTraceLevel() >= 1)
+                if(_instance.traceLevel() >= 1)
                 {
                     string s;
                     if(_adapterName == null)
                     {
-                        s = "ssl connection established\n" + _desc;
+                        s = protocol() + " connection established\n" + _desc;
                     }
                     else
                     {
-                        s = "accepted ssl connection\n" + _desc;
+                        s = "accepted " + protocol() + " connection\n" + _desc;
                     }
-                    _logger.trace(_instance.networkTraceCategory(), s);
+                    _instance.logger().trace(_instance.traceCategory(), s);
                 }
 
                 if(_instance.securityTraceLevel() >= 1)
@@ -693,7 +704,7 @@ namespace IceSSL
                     {
                         if(_instance.securityTraceLevel() >= 1)
                         {
-                            _logger.trace(_instance.securityTraceCategory(),
+                            _instance.logger().trace(_instance.securityTraceCategory(),
                                           "SSL certificate validation failed - client certificate not provided");
                         }
                         return false;
@@ -784,19 +795,21 @@ namespace IceSSL
                 {
                     if(message.Length > 0)
                     {
-                        _logger.trace(_instance.securityTraceCategory(), "SSL certificate validation failed:" +
-                                      message);
+                        _instance.logger().trace(_instance.securityTraceCategory(),
+                                                 "SSL certificate validation failed:" + message);
                     }
                     else
                     {
-                        _logger.trace(_instance.securityTraceCategory(), "SSL certificate validation failed");
+                        _instance.logger().trace(_instance.securityTraceCategory(),
+                                                 "SSL certificate validation failed");
                     }
                 }
                 return false;
             }
             else if(message.Length > 0 && _instance.securityTraceLevel() >= 1)
             {
-                _logger.trace(_instance.securityTraceCategory(), "SSL certificate validation status:" + message);
+                _instance.logger().trace(_instance.securityTraceCategory(), "SSL certificate validation status:" +
+                                         message);
             }
 
             return true;
@@ -826,7 +839,6 @@ namespace IceSSL
         private IPEndPoint _addr;
         private IceInternal.NetworkProxy _proxy;
         private SslStream _stream;
-        private Ice.Logger _logger;
         private string _desc;
         private int _verifyPeer;
         private int _maxSendPacketSize;
@@ -841,7 +853,7 @@ namespace IceSSL
         private const int StateNeedConnect = 0;
         private const int StateConnectPending = 1;
         private const int StateProxyConnectRequest = 2;
-        private const int StateProxyConnectRequestPending = 3; 
+        private const int StateProxyConnectRequestPending = 3;
         private const int StateNeedAuthenticate = 4;
         private const int StateAuthenticatePending = 5;
         private const int StateConnected = 6;
diff --git a/cs/test/Ice/background/Acceptor.cs b/cs/test/Ice/background/Acceptor.cs
index cc5d224a404..e9432d2580a 100644
--- a/cs/test/Ice/background/Acceptor.cs
+++ b/cs/test/Ice/background/Acceptor.cs
@@ -37,6 +37,11 @@ internal class Acceptor : IceInternal.Acceptor
         return new Transceiver(_acceptor.accept());
     }
 
+    public string protocol()
+    {
+        return _acceptor.protocol();
+    }
+
     public override string ToString()
     {
         return _acceptor.ToString();
diff --git a/cs/test/Ice/background/AllTests.cs b/cs/test/Ice/background/AllTests.cs
index 50535cd0f34..b2c8515ed22 100644
--- a/cs/test/Ice/background/AllTests.cs
+++ b/cs/test/Ice/background/AllTests.cs
@@ -86,6 +86,10 @@ public class AllTests
             _response.called();
         }
 
+        public void responseNoOp()
+        {
+        }
+
         public void noResponse()
         {
             test(false);
@@ -327,6 +331,40 @@ public class AllTests
         }
         Console.Out.WriteLine("ok");
 
+        bool ws = communicator.getProperties().getProperty("Ice.Default.Protocol").Equals("test-ws");
+        bool wss = communicator.getProperties().getProperty("Ice.Default.Protocol").Equals("test-wss");
+        if(!ws && !wss)
+        {
+            Console.Write("testing buffered transport... ");
+            Console.Out.Flush();
+
+            configuration.buffered(true);
+            backgroundController.buffered(true);
+            background.begin_op();
+            background.ice_getCachedConnection().close(true);
+            background.begin_op();
+
+            Ice.AsyncResult r;
+            OpAMICallback cb = new OpAMICallback();
+
+            for(int i = 0; i < 10000; ++i)
+            {
+                r = background.begin_op().whenCompleted(cb.responseNoOp, cb.noException);
+                if(i % 50 == 0)
+                {
+                    backgroundController.holdAdapter();
+                    backgroundController.resumeAdapter();
+                }
+                if(i % 100 == 0)
+                {
+                    r.waitForCompleted();
+                }
+            }
+            r.waitForCompleted();
+
+            Console.Out.WriteLine("ok");
+        }
+
         return background;
     }
 
diff --git a/cs/test/Ice/background/BackgroundControllerI.cs b/cs/test/Ice/background/BackgroundControllerI.cs
index 6f50af360ae..dd66e6aa932 100644
--- a/cs/test/Ice/background/BackgroundControllerI.cs
+++ b/cs/test/Ice/background/BackgroundControllerI.cs
@@ -92,6 +92,11 @@ internal class BackgroundControllerI : BackgroundControllerDisp_
         _configuration.writeException(enable ? new Ice.SocketException() : null);
     }
 
+    public override void buffered(bool enable, Ice.Current current)
+    {
+        _configuration.buffered(enable);
+    }
+
     internal BackgroundControllerI(Ice.ObjectAdapter adapter)
     {
         _adapter = adapter;
diff --git a/cs/test/Ice/background/Configuration.cs b/cs/test/Ice/background/Configuration.cs
index d76bcd527ac..2a9c51b3271 100644
--- a/cs/test/Ice/background/Configuration.cs
+++ b/cs/test/Ice/background/Configuration.cs
@@ -146,6 +146,16 @@ internal class Configuration
         }
     }
 
+    public void buffered(bool b)
+    {
+        _buffered = b;
+    }
+
+    public bool buffered()
+    {
+        return _buffered;
+    }
+
     static public Configuration getInstance()
     {
         return _instance;
@@ -158,6 +168,7 @@ internal class Configuration
     private Ice.LocalException _readException;
     private int _writeReadyCount;
     private Ice.LocalException _writeException;
+    private bool _buffered;
 
     private static Configuration _instance = new Configuration();
 }
diff --git a/cs/test/Ice/background/EndpointFactory.cs b/cs/test/Ice/background/EndpointFactory.cs
index 92e2e000f3b..f5b23b5c985 100644
--- a/cs/test/Ice/background/EndpointFactory.cs
+++ b/cs/test/Ice/background/EndpointFactory.cs
@@ -7,6 +7,9 @@
 //
 // **********************************************************************
 
+using System.Collections.Generic;
+using System.Diagnostics;
+
 internal class EndpointFactory : IceInternal.EndpointFactory
 {
     internal EndpointFactory(IceInternal.EndpointFactory factory)
@@ -24,20 +27,30 @@ internal class EndpointFactory : IceInternal.EndpointFactory
         return "test-" + _factory.protocol();
     }
 
-    public IceInternal.EndpointI create(string str, bool server)
+    public IceInternal.EndpointI create(List<string> args, bool server)
     {
-        return new EndpointI(_factory.create(str, server));
+        return new EndpointI(_factory.create(args, server));
     }
 
     public IceInternal.EndpointI read(IceInternal.BasicStream s)
     {
-        s.readShort();
-        return new EndpointI(_factory.read(s));
+        short type = s.readShort();
+        Debug.Assert(type == _factory.type());
+
+        s.startReadEncaps();
+        IceInternal.EndpointI endpoint = new EndpointI(_factory.read(s));
+        s.endReadEncaps();
+        return endpoint;
     }
 
     public void destroy()
     {
     }
 
+    public IceInternal.EndpointFactory clone(IceInternal.ProtocolInstance instance)
+    {
+        return this;
+    }
+
     private IceInternal.EndpointFactory _factory;
 }
diff --git a/cs/test/Ice/background/EndpointI.cs b/cs/test/Ice/background/EndpointI.cs
index 7c2dd1b8e93..9b091ebaf2e 100644
--- a/cs/test/Ice/background/EndpointI.cs
+++ b/cs/test/Ice/background/EndpointI.cs
@@ -20,18 +20,6 @@ internal class EndpointI : IceInternal.EndpointI
         _configuration = Configuration.getInstance();
     }
 
-    //
-    // Marshal the endpoint
-    //
-    public override void streamWrite(IceInternal.BasicStream s)
-    {
-        s.writeShort(type());
-        _endpoint.streamWrite(s);
-    }
-
-    //
-    // Convert the endpoint to its string form
-    //
     public override string ice_toString_()
     {
         return "test-" + _endpoint.ToString();
@@ -42,36 +30,29 @@ internal class EndpointI : IceInternal.EndpointI
         return _endpoint.getInfo();
     }
 
-    //
-    // Return the endpoint type
-    //
+    public override void streamWrite(IceInternal.BasicStream s)
+    {
+        s.startWriteEncaps();
+        s.writeShort(_endpoint.type());
+        _endpoint.streamWrite(s);
+        s.endWriteEncaps();
+    }
+
     public override short type()
     {
         return (short)(TYPE_BASE + _endpoint.type());
     }
 
-    //
-    // Return the protocol name;
-    //
     public override string protocol()
     {
         return _endpoint.protocol();
     }
 
-    //
-    // Return the timeout for the endpoint in milliseconds. 0 means
-    // non-blocking, -1 means no timeout.
-    //
     public override int timeout()
     {
         return _endpoint.timeout();
     }
 
-    //
-    // Return a new endpoint with a different timeout value, provided
-    // that timeouts are supported by the endpoint. Otherwise the same
-    // endpoint is returned.
-    //
     public override IceInternal.EndpointI timeout(int timeout)
     {
         IceInternal.EndpointI endpoint = _endpoint.timeout(timeout);
@@ -85,9 +66,11 @@ internal class EndpointI : IceInternal.EndpointI
         }
     }
 
-    //
-    // Return a new endpoint with a different connection id.
-    //
+    public override string connectionId()
+    {
+        return _endpoint.connectionId();
+    }
+
     public override IceInternal.EndpointI connectionId(string connectionId)
     {
         IceInternal.EndpointI endpoint = _endpoint.connectionId(connectionId);
@@ -101,20 +84,11 @@ internal class EndpointI : IceInternal.EndpointI
         }
     }
 
-    //
-    // Return true if the endpoints support bzip2 compress, or false
-    // otherwise.
-    //
     public override bool compress()
     {
         return _endpoint.compress();
     }
 
-    //
-    // Return a new endpoint with a different compression value,
-    // provided that compression is supported by the
-    // endpoint. Otherwise the same endpoint is returned.
-    //
     public override IceInternal.EndpointI compress(bool compress)
     {
         IceInternal.EndpointI endpoint = _endpoint.compress(compress);
@@ -128,29 +102,16 @@ internal class EndpointI : IceInternal.EndpointI
         }
     }
 
-    //
-    // Return true if the endpoint is datagram-based.
-    //
     public override bool datagram()
     {
         return _endpoint.datagram();
     }
 
-    //
-    // Return true if the endpoint is secure.
-    //
     public override bool secure()
     {
         return _endpoint.secure();
     }
 
-    //
-    // Return a server side transceiver for this endpoint, or null if a
-    // transceiver can only be created by an acceptor. In case a
-    // transceiver is created, this operation also returns a new
-    // "effective" endpoint, which might differ from this endpoint,
-    // for example, if a dynamic port number is assigned.
-    //
     public override IceInternal.Transceiver transceiver(ref IceInternal.EndpointI endpoint)
     {
         IceInternal.Transceiver transceiver = _endpoint.transceiver(ref endpoint);
@@ -173,10 +134,6 @@ internal class EndpointI : IceInternal.EndpointI
         }
     }
 
-    //
-    // Return connectors for this endpoint, or empty list if no connector
-    // is available.
-    //
     public override List<IceInternal.Connector> connectors(Ice.EndpointSelectionType selType)
     {
         _configuration.checkConnectorsException();
@@ -257,14 +214,16 @@ internal class EndpointI : IceInternal.EndpointI
         return testEndpoint._endpoint.equivalent(_endpoint);
     }
 
+    public override string options()
+    {
+        return _endpoint.options();
+    }
+
     public override int GetHashCode()
     {
         return _endpoint.GetHashCode();
     }
 
-    //
-    // Compare endpoints for sorting purposes
-    //
     public override int CompareTo(IceInternal.EndpointI obj)
     {
         EndpointI p = null;
diff --git a/cs/test/Ice/background/Test.ice b/cs/test/Ice/background/Test.ice
index 2749525fc48..e05437fcf4c 100644
--- a/cs/test/Ice/background/Test.ice
+++ b/cs/test/Ice/background/Test.ice
@@ -10,6 +10,7 @@
 #pragma once
 
 #include <Ice/BuiltinSequences.ice>
+#include <Ice/Endpoint.ice>
 
 module Test
 {
@@ -37,6 +38,9 @@ interface BackgroundController
 
     void writeReady(bool enable);
     void writeException(bool enable);
+
+    void buffered(bool enable);
 };
 
 };
+
diff --git a/cs/test/Ice/background/Transceiver.cs b/cs/test/Ice/background/Transceiver.cs
index dad661ef88e..7dcc31e729b 100644
--- a/cs/test/Ice/background/Transceiver.cs
+++ b/cs/test/Ice/background/Transceiver.cs
@@ -8,60 +8,96 @@
 // **********************************************************************
 
 using System;
+using System.Diagnostics;
 using System.Net.Sockets;
 
 internal class Transceiver : IceInternal.Transceiver
 {
-    public int initialize()
+    public int initialize(IceInternal.Buffer readBuffer, IceInternal.Buffer writeBuffer, ref bool hasMoreData)
     {
         _configuration.checkInitializeException();
         if(!_initialized)
         {
-            int s = _transceiver.initialize();
-            if(s != IceInternal.SocketOperation.None)
+            int status = _transceiver.initialize(readBuffer, writeBuffer, ref hasMoreData);
+            if(status != IceInternal.SocketOperation.None)
             {
-                return s;
+                return status;
             }
             _initialized = true;
         }
         return IceInternal.SocketOperation.None;
     }
 
+    public int closing(bool initiator, Ice.LocalException ex)
+    {
+        return _transceiver.closing(initiator, ex);
+    }
+
     public void close()
     {
         _transceiver.close();
     }
 
-    public bool write(IceInternal.Buffer buf)
+    public int write(IceInternal.Buffer buf)
     {
-        if(!_initialized)
+        if(!_configuration.writeReady() && buf.b.hasRemaining())
         {
-            throw new Ice.SocketException();
-        }
-
-        if(!_configuration.writeReady())
-        {
-            return false;
+            return IceInternal.SocketOperation.Write;
         }
 
         _configuration.checkWriteException();
         return _transceiver.write(buf);
     }
 
-    public bool read(IceInternal.Buffer buf)
+    public int read(IceInternal.Buffer buf, ref bool hasMoreData)
     {
-        if(!_initialized)
+        if(!_configuration.readReady() && buf.b.hasRemaining())
         {
-            throw new Ice.SocketException();
+            return IceInternal.SocketOperation.Read;
         }
 
-        if(!_configuration.readReady())
+        _configuration.checkReadException();
+
+        if(_buffered)
         {
-            return false;
+            while(buf.b.hasRemaining())
+            {
+                if(_readBufferPos == _readBuffer.b.position())
+                {
+                    _readBufferPos = 0;
+                    _readBuffer.b.position(0);
+                    _transceiver.read(_readBuffer, ref hasMoreData);
+                    if(_readBufferPos == _readBuffer.b.position())
+                    {
+                        hasMoreData = false;
+                        return IceInternal.SocketOperation.Read;
+                    }
+                }
+
+                int pos = _readBuffer.b.position();
+                Debug.Assert(pos > _readBufferPos);
+                int requested = buf.b.remaining();
+                int available = pos - _readBufferPos;
+                Debug.Assert(available > 0);
+                if(available >= requested)
+                {
+                    available = requested;
+                }
+
+                byte[] arr = new byte[available];
+                _readBuffer.b.position(_readBufferPos);
+                _readBuffer.b.get(arr);
+                buf.b.put(arr);
+                _readBufferPos += available;
+                _readBuffer.b.position(pos);
+            }
+            hasMoreData = _readBufferPos < _readBuffer.b.position();
+            return IceInternal.SocketOperation.None;
+        }
+        else
+        {
+            return _transceiver.read(buf, ref hasMoreData);
         }
-
-        _configuration.checkReadException();
-        return _transceiver.read(buf);
     }
 
     public bool startRead(IceInternal.Buffer buf, IceInternal.AsyncCallback callback, object state)
@@ -70,13 +106,76 @@ internal class Transceiver : IceInternal.Transceiver
         {
             _configuration.checkReadException(); // Only raise if we're configured to read now.
         }
-        return _transceiver.startRead(buf, callback, state);
+        if(_buffered)
+        {
+            int pos = _readBuffer.b.position();
+            int available = pos - _readBufferPos;
+            if(available > 0)
+            {
+                int requested = buf.b.remaining();
+                if(available >= requested)
+                {
+                    available = requested;
+                }
+
+                byte[] arr = new byte[available];
+                _readBuffer.b.position(_readBufferPos);
+                _readBuffer.b.get(arr);
+                buf.b.put(arr);
+                _readBufferPos += available;
+                _readBuffer.b.position(pos);
+            }
+
+            if(_readBufferPos == _readBuffer.b.position() && buf.b.hasRemaining())
+            {
+                _readBufferPos = 0;
+                _readBuffer.b.position(0);
+                return _transceiver.startRead(_readBuffer, callback, state);
+            }
+            else
+            {
+                Debug.Assert(!buf.b.hasRemaining());
+                return true; // Completed synchronously
+            }
+        }
+        else
+        {
+            return _transceiver.startRead(buf, callback, state);
+        }
     }
 
     public void finishRead(IceInternal.Buffer buf)
     {
         _configuration.checkReadException();
-        _transceiver.finishRead(buf);
+        if(_buffered)
+        {
+            if(buf.b.hasRemaining())
+            {
+                _transceiver.finishRead(_readBuffer);
+
+                int pos = _readBuffer.b.position();
+                int requested = buf.b.remaining();
+                int available = pos - _readBufferPos;
+                if(available > 0)
+                {
+                    if(available >= requested)
+                    {
+                        available = requested;
+                    }
+
+                    byte[] arr = new byte[available];
+                    _readBuffer.b.position(_readBufferPos);
+                    _readBuffer.b.get(arr);
+                    buf.b.put(arr);
+                    _readBufferPos += available;
+                    _readBuffer.b.position(pos);
+                }
+            }
+        }
+        else
+        {
+            _transceiver.finishRead(buf);
+        }
     }
 
     public bool startWrite(IceInternal.Buffer buf, IceInternal.AsyncCallback callback, object state, out bool completed)
@@ -91,9 +190,9 @@ internal class Transceiver : IceInternal.Transceiver
         _transceiver.finishWrite(buf);
     }
 
-    public string type()
+    public string protocol()
     {
-        return "test-" + _transceiver.type();
+        return "test-" + _transceiver.protocol();
     }
 
     public Ice.ConnectionInfo getInfo()
@@ -118,9 +217,18 @@ internal class Transceiver : IceInternal.Transceiver
     {
         _transceiver = transceiver;
         _configuration = Configuration.getInstance();
+        _initialized = false;
+        _readBuffer = new IceInternal.Buffer(100 * 1024);
+        _readBuffer.resize(1024 * 8, true); // 8KB buffer
+        _readBuffer.b.position(0);
+        _readBufferPos = 0;
+        _buffered = _configuration.buffered();
     }
 
     private IceInternal.Transceiver _transceiver;
     private Configuration _configuration;
-    private bool _initialized = false;
+    private bool _initialized;
+    private IceInternal.Buffer _readBuffer;
+    private int _readBufferPos;
+    private bool _buffered;
 }
diff --git a/java/src/Ice/ConnectionI.java b/java/src/Ice/ConnectionI.java
index fb2c0ce8a33..a39905470ac 100644
--- a/java/src/Ice/ConnectionI.java
+++ b/java/src/Ice/ConnectionI.java
@@ -2348,7 +2348,7 @@ public final class ConnectionI extends IceInternal.EventHandler implements Conne
         {
             return IceInternal.SocketOperation.None;
         }
-        else if(_state == StateClosingPending && _writeStream.pos() == _writeStream.size())
+        else if(_state == StateClosingPending && _writeStream.pos() == 0)
         {
             // Message wasn't sent, empty the _writeStream, we're not going to send more data.
             OutgoingMessage message = _sendStreams.getFirst();
diff --git a/java/src/IceInternal/IPEndpointI.java b/java/src/IceInternal/IPEndpointI.java
index 7c860106754..e887fb95770 100644
--- a/java/src/IceInternal/IPEndpointI.java
+++ b/java/src/IceInternal/IPEndpointI.java
@@ -151,6 +151,7 @@ public abstract class IPEndpointI extends EndpointI
             _hashValue = 5381;
             _hashValue = HashUtil.hashAdd(_hashValue, type());
             _hashValue = hashInit(_hashValue);
+            _hashInitialized = true;
         }
         return _hashValue;
     }
diff --git a/java/src/IceInternal/OutgoingConnectionFactory.java b/java/src/IceInternal/OutgoingConnectionFactory.java
index 53a1abbfc90..f9e5a50b57a 100644
--- a/java/src/IceInternal/OutgoingConnectionFactory.java
+++ b/java/src/IceInternal/OutgoingConnectionFactory.java
@@ -28,20 +28,6 @@ public final class OutgoingConnectionFactory
             list.add(value);
         }
 
-        /*
-        public void
-        removeElementWithValue(K key, V value)
-        {
-            java.util.List<V> list = this.get(key);
-            assert(list != null);
-            list.remove(value);
-            if(list.isEmpty())
-            {
-                this.remove(key);
-            }
-        }
-        */
-
         public boolean
         removeElementWithValue(K key, V value)
         {
@@ -54,7 +40,7 @@ public final class OutgoingConnectionFactory
             }
             return v;
         }
-    };
+    }
 
     interface CreateConnectionCallback
     {
diff --git a/java/src/IceInternal/TcpAcceptor.java b/java/src/IceInternal/TcpAcceptor.java
index d8f35bb625a..ef20c146dac 100644
--- a/java/src/IceInternal/TcpAcceptor.java
+++ b/java/src/IceInternal/TcpAcceptor.java
@@ -11,18 +11,16 @@ package IceInternal;
 
 class TcpAcceptor implements Acceptor
 {
-    public java.nio.channels.ServerSocketChannel
-    fd()
+    public java.nio.channels.ServerSocketChannel fd()
     {
         return _fd;
     }
 
-    public void
-    close()
+    public void close()
     {
         if(_instance.traceLevel() >= 1)
         {
-            String s = "stopping to accept tcp connections at " + toString();
+            String s = "stopping to accept " + protocol() + " connections at " + toString();
             _instance.logger().trace(_instance.traceCategory(), s);
         }
 
@@ -31,17 +29,16 @@ class TcpAcceptor implements Acceptor
         _fd = null;
     }
 
-    public void
-    listen()
+    public void listen()
     {
         // Nothing to do.
 
         if(_instance.traceLevel() >= 1)
         {
-            StringBuffer s = new StringBuffer("listening for tcp connections at ");
+            StringBuffer s = new StringBuffer("listening for " + protocol() + " connections at ");
             s.append(toString());
 
-            java.util.List<String> interfaces = 
+            java.util.List<String> interfaces =
                 Network.getHostsForEndpointExpand(_addr.getAddress().getHostAddress(), _instance.protocolSupport(),
                                                   true);
             if(!interfaces.isEmpty())
@@ -53,8 +50,7 @@ class TcpAcceptor implements Acceptor
         }
     }
 
-    public Transceiver
-    accept()
+    public Transceiver accept()
     {
         java.nio.channels.SocketChannel fd = Network.doAccept(_fd);
         Network.setBlock(fd, false);
@@ -62,27 +58,24 @@ class TcpAcceptor implements Acceptor
 
         if(_instance.traceLevel() >= 1)
         {
-            String s = "accepted tcp connection\n" + Network.fdToString(fd);
+            String s = "accepted " + protocol() + " connection\n" + Network.fdToString(fd);
             _instance.logger().trace(_instance.traceCategory(), s);
         }
 
         return new TcpTransceiver(_instance, fd);
     }
 
-    public String
-    protocol()
+    public String protocol()
     {
         return _instance.protocol();
     }
 
-    public String
-    toString()
+    public String toString()
     {
         return Network.addrToString(_addr);
     }
 
-    int
-    effectivePort()
+    int effectivePort()
     {
         return _addr.getPort();
     }
@@ -100,24 +93,24 @@ class TcpAcceptor implements Acceptor
             if(!System.getProperty("os.name").startsWith("Windows"))
             {
                 //
-                // Enable SO_REUSEADDR on Unix platforms to allow
-                // re-using the socket even if it's in the TIME_WAIT
-                // state. On Windows, this doesn't appear to be
-                // necessary and enabling SO_REUSEADDR would actually
-                // not be a good thing since it allows a second
-                // process to bind to an address even it's already
-                // bound by another process.
+                // Enable SO_REUSEADDR on Unix platforms to allow re-using the
+                // socket even if it's in the TIME_WAIT state. On Windows,
+                // this doesn't appear to be necessary and enabling
+                // SO_REUSEADDR would actually not be a good thing since it
+                // allows a second process to bind to an address even it's
+                // already bound by another process.
                 //
-                // TODO: using SO_EXCLUSIVEADDRUSE on Windows would
-                // probably be better but it's only supported by recent
-                // Windows versions (XP SP2, Windows Server 2003).
+                // TODO: using SO_EXCLUSIVEADDRUSE on Windows would probably
+                // be better but it's only supported by recent Windows
+                // versions (XP SP2, Windows Server 2003).
                 //
                 Network.setReuseAddress(_fd, true);
             }
+
             _addr = Network.getAddressForServer(host, port, instance.protocolSupport(), instance.preferIPv6());
             if(instance.traceLevel() >= 2)
             {
-                String s = "attempting to bind to tcp socket " + toString();
+                String s = "attempting to bind to " + protocol() + " socket " + toString();
                 instance.logger().trace(instance.traceCategory(), s);
             }
             _addr = Network.doBind(_fd, _addr, _backlog);
@@ -129,8 +122,7 @@ class TcpAcceptor implements Acceptor
         }
     }
 
-    protected synchronized void
-    finalize()
+    protected synchronized void finalize()
         throws Throwable
     {
         try
diff --git a/java/src/IceInternal/UdpConnector.java b/java/src/IceInternal/UdpConnector.java
index 054014efc2c..94ddf2d14cd 100644
--- a/java/src/IceInternal/UdpConnector.java
+++ b/java/src/IceInternal/UdpConnector.java
@@ -38,7 +38,7 @@ final class UdpConnector implements Connector
     }
 
     //
-    // Only for use by TcpEndpoint
+    // Only for use by UdpEndpointI
     //
     UdpConnector(ProtocolInstance instance, java.net.InetSocketAddress addr, String mcastInterface, int mcastTtl,
                  String connectionId)
diff --git a/java/src/IceInternal/UdpTransceiver.java b/java/src/IceInternal/UdpTransceiver.java
index 15f1683cf4e..d8344adb130 100644
--- a/java/src/IceInternal/UdpTransceiver.java
+++ b/java/src/IceInternal/UdpTransceiver.java
@@ -66,6 +66,11 @@ final class UdpTransceiver implements Transceiver
             return SocketOperation.Write;
         }
 
+        if(!buf.b.hasRemaining())
+        {
+            return SocketOperation.None;
+        }
+
         assert(buf.b.position() == 0);
         assert(_fd != null && _state >= StateConnected);
 
@@ -127,6 +132,11 @@ final class UdpTransceiver implements Transceiver
     @SuppressWarnings("deprecation")
     public int read(Buffer buf, Ice.BooleanHolder moreData)
     {
+        if(!buf.b.hasRemaining())
+        {
+            return SocketOperation.None;
+        }
+
         assert(buf.b.position() == 0);
 
         final int packetSize = java.lang.Math.min(_maxPacketSize, _rcvSize - _udpOverhead);
diff --git a/java/test/Ice/background/AllTests.java b/java/test/Ice/background/AllTests.java
index 45bb92f6a05..e029f2a8056 100644
--- a/java/test/Ice/background/AllTests.java
+++ b/java/test/Ice/background/AllTests.java
@@ -152,6 +152,26 @@ public class AllTests
         private Callback _sent = new Callback();
     }
 
+    private static class OpAMICallbackNoOp extends Callback_Background_op
+    {
+        @Override
+        public void response()
+        {
+        }
+
+        @Override
+        public void exception(Ice.LocalException ex)
+        {
+            ex.printStackTrace();
+            test(false);
+        }
+
+        @Override
+        public void sent(boolean ss)
+        {
+        }
+    }
+
     private static class NoResponse extends Callback_Background_opWithPayload
     {
         @Override
@@ -371,6 +391,40 @@ public class AllTests
         }
         out.println("ok");
 
+        final boolean ws = communicator.getProperties().getProperty("Ice.Default.Protocol").equals("test-ws");
+        final boolean wss = communicator.getProperties().getProperty("Ice.Default.Protocol").equals("test-wss");
+        if(!ws && !wss)
+        {
+            out.print("testing buffered transport... ");
+            out.flush();
+
+            configuration.buffered(true);
+            backgroundController.buffered(true);
+            background.begin_op();
+            background.ice_getCachedConnection().close(true);
+            background.begin_op();
+
+            Ice.AsyncResult r = null;
+            OpAMICallbackNoOp cb = new OpAMICallbackNoOp();
+
+            for(int i = 0; i < 10000; ++i)
+            {
+                r = background.begin_op(cb);
+                if(i % 50 == 0)
+                {
+                    backgroundController.holdAdapter();
+                    backgroundController.resumeAdapter();
+                }
+                if(i % 100 == 0)
+                {
+                    r.waitForCompleted();
+                }
+            }
+            r.waitForCompleted();
+
+            out.println("ok");
+        }
+
         return background;
     }
 
diff --git a/java/test/Ice/background/BackgroundControllerI.java b/java/test/Ice/background/BackgroundControllerI.java
index 594a623d131..64cefee73ca 100644
--- a/java/test/Ice/background/BackgroundControllerI.java
+++ b/java/test/Ice/background/BackgroundControllerI.java
@@ -88,6 +88,12 @@ class BackgroundControllerI extends _BackgroundControllerDisp
     {
         _configuration.writeException(enable ? new Ice.SocketException() : null);
     }
+
+    public void
+    buffered(boolean enable, Ice.Current current)
+    {
+        _configuration.buffered(enable);
+    }
     
     public
     BackgroundControllerI(Configuration configuration, Ice.ObjectAdapter adapter)
diff --git a/java/test/Ice/background/Test.ice b/java/test/Ice/background/Test.ice
index 95d72cb42b6..b612eb4d280 100644
--- a/java/test/Ice/background/Test.ice
+++ b/java/test/Ice/background/Test.ice
@@ -18,8 +18,8 @@ module Test
 
 interface Background
 {
-    ["ami"] void op();
-    ["ami"] void opWithPayload(Ice::ByteSeq seq);
+    void op();
+    void opWithPayload(Ice::ByteSeq seq);
 
     void shutdown();
 };
@@ -28,7 +28,7 @@ interface BackgroundController
 {
     void pauseCall(string call);
     void resumeCall(string call);
-    
+
     void holdAdapter();
     void resumeAdapter();
 
@@ -40,6 +40,8 @@ interface BackgroundController
 
     void writeReady(bool enable);
     void writeException(bool enable);
+
+    void buffered(bool enable);
 };
 
 };
diff --git a/java/test/Ice/background/Transceiver.java b/java/test/Ice/background/Transceiver.java
index 36a0b85a6d2..a16eb335cfe 100644
--- a/java/test/Ice/background/Transceiver.java
+++ b/java/test/Ice/background/Transceiver.java
@@ -105,9 +105,10 @@ final class Transceiver implements IceInternal.Transceiver
                         return IceInternal.SocketOperation.Read;
                     }
                 }
-                assert(_readBuffer.b.position() > _readBufferPos);
-                int requested = buf.b.remaining();
-                int available = _readBuffer.b.position() - _readBufferPos;
+                final int pos = _readBuffer.b.position();
+                assert(pos > _readBufferPos);
+                final int requested = buf.b.remaining();
+                int available = pos - _readBufferPos;
                 assert(available > 0);
                 if(available >= requested)
                 {
@@ -115,9 +116,11 @@ final class Transceiver implements IceInternal.Transceiver
                 }
 
                 byte[] arr = new byte[available];
+                _readBuffer.b.position(_readBufferPos);
                 _readBuffer.b.get(arr);
                 buf.b.put(arr);
                 _readBufferPos += available;
+                _readBuffer.b.position(pos);
             }
             moreData.value = _readBufferPos < _readBuffer.b.position();
             return IceInternal.SocketOperation.None;