Description

Simple implementation of hole punching to produce direct connection between two clients that may be behind NAT using mediator server.

HowTo

1. Run direct-chatter-mediator on dedicated server with static ip to which both clients can connect
2. Run direct-chatter-client on both clients with mediator IP as argument
3. If everything is ok clients will be connected between each other directly

Problems

1. Clients must be behind different NAT device (if you are running both the clients under same NAT device then it may not work because not all NAT devices support hair pinning i.e, both clients send packets to NAT's external IP which needs to be passed to itself)
2. Some NAT's can behave differently, opened external port for CLIENT1->MEDIATOR (which mediator is sending to CLIENT2) will be different for CLIENT1->CLIENT2 and whole hole punching wont work