Feature request: compress away IP and port from each HTTP Datagram

[DavidSchinazi]

From Ben Schwartz on the list:

In IPv6, the proposed header adds 19 bytes of overhead per packet. For Opus compressed audio, this represents >50% of the media bandwidth for low-bitrate VoIP (20ms frames, 12kbps) or interactive music (2.5ms frames, 112kbps).

The natural benchmark for this draft is TURN. To reduce per-packet overhead, TURN offers a form of "header compression" called Channels (https://datatracker.ietf.org/doc/html/rfc8656#section-3.5). The equivalent thing for this draft would be to define a dynamic context allocation option.

[DavidSchinazi]

This makes sense. I would imagine performing this by using a capsule to register a context ID that maps to a given (IP version, IP address, UDP port) tuple