I don't understand why. I'm not a networking expert but I have some experience with networking... I mean, I've already tried a proof-of-concept out with a computer behind a NAT router and it worked fine.
Think about 2 devices (A,B) behind routers in different networks. Connections from A end up on B's router since there's no existing connection to match and connections from B end up on A's router. Unless you explicitly configure port forwarding B will never know that A is calling him.
Yeah - that will do, but the TURN operator is a third party. I commented about the situation assuming Joeboy meant P2P connection without Skype or anyone else Skype-like (the URL is the only thing needed). If you're ok with someone else providing TURN and making money on it in some way to pay for the bandwidth, then yeah - that's enough.
I'll be honest, I'm currently abusing the STUN servers that Google uses in their own WebRTC examples and will need to evaluate my own options. I was under the impression that STUN could be used to establish a connection that from then forward was able to be only peer to peer after the connection through the NAT had been established.
