Client disconnects after a few seconds

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Client connects to a remote server.
2. Client receives/sends data normally
3. Client disconnects abruptly

What is the expected output? What do you see instead?
Client stays connected.

What version of the product are you using? On what operating system?
lidgren latest version pulled from github. Client is on Mac OS X 10.10, server 
on Ubuntu 12.04

Please provide any additional information below.
When running the server locally, everything works as intended.

Also, when the server runs locally I see the message "Initiated average 
roundtrip time etc. etc." on the client's log. However when the server is 
remote, no such message is shown.

Finally, for the few 3-5 seconds before the connection drops, data are sent and 
received normally between the client and the server.

Original issue reported on code.google.com by jkelesi...@gmail.com on 26 Jul 2015 at 1:56

[GoogleCodeExporter]

Do the samples exhibit the same problem? I don't have access to a mac for 
testing, so more information would be appreciated. Are there any exceptions 
swallowed or other debug/verbose output?

Original comment by lidg...@gmail.com on 26 Jul 2015 at 6:49

[GoogleCodeExporter]

Yes, the samples exhibit the same problem.

I monitored the traffic on the client machine and wireshark reports a lot of 
icmp packets where the port is unreachable from the client to the server.

The issue disappears when I enable UPnP on the router that the client gets to 
the Internet.

Original comment by jkelesi...@gmail.com on 26 Jul 2015 at 10:19

[GoogleCodeExporter]

Forgot to mention, there are no messages on the server. On the client when it 
disconnects, I get a status changed - disconnected message.

When performing a ReadString on that message it says "Connec". Wireshark on the 
other hand reports that the payload of that message contains "Connection timed 
out".

Original comment by jkelesi...@gmail.com on 26 Jul 2015 at 10:22