[bruun]

Tip if you feel like you have to maintain a lot of infrastructure with your TURN server: You can scrap your STUN server, since TURN is an extension of STUN. The TURN server will produce the same server reflex candidate as your STUN server.

What port(s) were you using on your TURN server endpoint? Keep in mind that port 80 is often filtered, and many corporate networks often block non-HTTP(S) ports. At the WebRTC-utilizing service https://appear.in, we have found that using port 443 plays nicely with most restrictive networks.

[bryanpaluch]

TURN over port 443 specifically using TCP not UDP should get around most firewalls.

If a provider is using DPI and trying to disable ssl network wide, you will still have a problem.