问题
My need is to communicate between 2 client behind NAT using http tunneling. Is it possible? What all setup is needed to achieve this (like http proxy server etc.)? Is there any library or sample code available for implementing http tunneling over TCP in C#?
回答1:
It might be possible for you to use this library: http://granados.sourceforge.net/
It supports port forwarding (tunneling in this case), but I haven't tried it myself.
It's an SSH library... so if you can set up an SSH server on either end of the connection you'll be able to establish an SSH connection and create a tunnel.
来源：https://stackoverflow.com/questions/2272482/http-tunneling-to-pass-firewall-in-c-sharp-tcp