I have successfully compiled source code of doubango opentelepresence system (An open source video conference MCU) and successfully tested. I can make video calls through desktop version and using webrtc (sipml5 client) with Chrome and Firefox (with some modifications because the sipml5 was not compatible with newer versions).
Now my problem is with NAT traversal. I want to make video calls between clients behind NAT using turn server. The MCU server is behind NAT (SIP port is on public IP using port forwarding and tcp sip and ws connection is available). I have installed coturn Turn Server on a ubuntu system, and configured it using command line as like why the turn server does not support for the tcp connection. The turn server ports is open on public ip. I have also tested both udp and tcp but not successful.
On the mcu, ice, stun and turn is enabled. I have set turn server url and credentials correctly and the mcu can successfully communicate with turn server. Also webrtc on the browsers can successfully communicate with turn server (I say successful communication, because I can see candidates are being generated).
I have two major problems:
- For some reasons related to firewall, I prefer to use only tcp relay. But in test environment, I have tested both with udp and tcp but not successful. It seems doubango opentelepresence does not support relayed tcp, because I cannot see any candidate with relayed tcp (there are udp relayed candidates).
- What is wrong with my configuration which I was never successful on making a call. The ICE candidates are generated with public ip, but their state is always failed or frozen (what does frozen mean!). If you have any suggestions, let me know and try. I can test and report results here until reach a successful video call.
Yellow parts are public IP address (a valid IP address accessible on the internet for all clients).