remote side is restarting ICE issues

Couple of issues:

1) We embed the ufrag/password in the “start” method of the ICE transport. If the remote side is restarting, does that mean we need to restart too? Presumable we have to at minimum flush all candidates. But we can’t call start again to update the remote ufrag/password

2) When I asked about restart causing a retargeting to a new device (i.e. new DTLS credentials), I’ve received conflicting information. I heard that retargeting only applies to something like TURN vs local candidates not a change in device. However, apparently a SIP re-invite can mean targeting to an entirely new device. Thus we may receive new ufrag/password and assuming it’s a remote restart but it’s actually a retarget to a new device. We have no way to know the difference thus we must always assume it’s a new device and redo the DTLS handshakes.

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Robin Raymond