Communication between two computers without opening ports, using a third computer to set up the connection

Question

Let\'s say I have a server, and two clients connected to it. (via TCP, but it doesn\'t matter)

My goal is to allow a direct connection between those two clients. This is

Answer 1

I'm not aware of any way to reliably punch through firewalls for TCP, but there's a similar method for UDP traffic that's pretty well documented:

• http://en.wikipedia.org/wiki/STUN

• http://en.wikipedia.org/wiki/UDP_hole_punching