This is a wonderfully succinct description of the topic and probably the most approachable explanation I have read. Really interesting that this was written in

This is a wonderfully succinct description of the topic and probably the most approachable explanation I have read. Really interesting that this was written in 2005 since the concepts described form the basis of how the later WebRTC and its supporting infrastructure STUN/TURN work. As brilliant a hack as hole punching is I hope someday we can move to a world of IPv6 where it is no longer necessary.