Can P2P be done without port forwarding?
I was making a simple file transfer program through IRC and when I was reading up I saw that IRC when sharing a file creates a direct connection between the two users independent of the server (DCC, Direct Client Connect). After searching a while I have found this: Direct Connect and Advanced Direct Connect . None of these pages answer this question that I can't get out of my head: Is P2P data transfer possible without any user doing a special port-forward? An intermediate server which helps set up the connection (as in the IRC examples) is allowed. The data transfer itself must be independent