I realize that media will run over UDP with a webRTC connection, but what about signaling? Does it require TCP or can it run over UDP? All of the examples using SIPJS I could find run the signaling over a websocket (therefor TCP).
What about if the signaling is encrypted - can it still run over UDP? (I assume it's just SIPS)
You can't, or at last not directly. SIP.js is about running SIP signaling in browsers. From a standard perspective, it uses SIP over WebSocket (https://datatracker.ietf.org/doc/html/rfc7118) which means running over TCP.
The answer changes a bit with HTTP/3 which runs on either UDP or TCP. Once WebSockets are standardized there (see https://datatracker.ietf.org/doc/html/rfc9220), then you will be able to say that SIP.js can run over UDP as well.
That said, it won't be in the same way that SIP runs over UDP outside of the browser as it will be done over a higher abstraction layer that is WebSocket.
My question though, would be - why does this even matter to you?
