[AVTCORE] Review of draft-engelbart-rtp-over-quic (David Schinazi)

[Bernard Aboba <[e-mail]>]

Forwarded from David:

I quickly skimmed this and I think the authors misunderstand a fundamental
point: you cannot multiplex two separate application protocols over one
QUIC connection. During the QUIC handshake, an ALPN token is negotiated and
that protocol is the only one in use for the lifetime of this connection.
If you want to simultaneously run RTP-over-QUIC and WebTransport, you have
two options:

1) define RTP-over-HTTP/3. That way you have one QUIC connection with
ALPN=h3 and then you can run as many RTP or WebTransport sessions on top.
2) use two distinct QUIC connections, one for RTP and one for
WebTransport-over-HTTP/3. They can be on the same socket and demultiplexed
using the QUIC connection ID

If you go the RTP-over-QUIC route, then the document that defines it gets
to define what the payload of datagram frames contains. They can choose to
use a flow identifier and can define its semantics to be whatever they
want. They can also skip flow identifiers and use something else instead.