[mike__t]

Turn servers can also send data over TCP (e.g. https://code.google.com/p/rfc5766-turn-server/ does). The browser also needs to support this option as well; Chrome seems to with a ";transport=tcp" at the send of the turn server configuration url.

[kodablah]

My mistake, I see that now [1]. It seems both sides need to specify that which isn't a problem. Also seems FF is on board [2][3].

1 - https://groups.google.com/forum/#!topic/turn-server-project-... 2 - https://bugzilla.mozilla.org/show_bug.cgi?id=891551 3 - https://bugzilla.mozilla.org/show_bug.cgi?id=906968