Connectivity, we at TokBox believe, is one of the cornerstones of real-time communication applications. So we are happy to announce that we now support TURN over TCP.
There are several technologies which are used to help establish connectivity in WebRTC. The first mechanism is using a protocol called STUN. STUN uses a ping-pong mechanism to find the public IP of a client end-point so that a peer-to-peer session can be established and one can traverse a firewall. While this is useful in a number of scenarios, there are cases where one could be behind symmetric NATs, where STUN does not suffice. TURN helps in these cases. TURN is a mechanism by which real-time media can be relayed through a TURN server to punch through firewalls. OpenTok seamlessly supports STUN and TURN so a developer doesn’t have to worry about how to setup up these servers, scale them, establish connectivity etc.