We had a project with this aim a few years ago, but it never got to
anything more than a proof of concept. I pushed it here in case you
want to take a look:
The idea is to multiplex based on the ufrag in STUN binding requests,
with backend bridges encoding their address in their ufrag.
However, the current recommendation is to not use ICE/TCP in favor of
TURN/TLS. We’ve been looking for a solution for demultiplexing
TURN/TLS and HTTPS, and while it’s doable we don’t have anything
ready, so you will need one additional IP address for the TURN server.
Hope this helps,