Torgeek
How does NAT hole punching work?
Each client tries to connect to its peer through the specified IP address and port that the peer's firewall has opened for the server. The new connection attempt punches a hole in the client's firewall as the endpoint now becomes open to receive a response from its peer.
What is port punching?
UDP hole punching establishes connectivity between two hosts communicating across one or more network address translators. Typically, third-party hosts on the public transit network are used to establish UDP port states that may be used for direct communications between the communicating hosts.
