Do TCP sockets automatically close after some time if no data is sent?

Question

I have a client server situation where the client opens a TCP socket to the server, and sometimes long periods of time will pass with no data being sent between them. I have enc

Answer 1

There is a timeout built in to TCP but you can adjust it, See SendTimeout and ReciveTimeout of the Socket class, but I have a suspiciouion that is not your problem. A NAT router may also have a expiration time for TCP connections before it removes it from it's port forwarding table. If no traffic passes within the time of that timeout on the router it will block all incoming traffic (as it cleared the forwarding information from it's memory so it does not know what computer to send the traffic to), also the outgoing connection will likely have a different source port so the server may not recognize it as the same connection.