Re: [rtcweb] Clarification on simulcast and RID and RepairedRtpStreamId

Iñaki Baz Castillo <ibc@aliax.net> Mon, 03 December 2018 21:26 UTC

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From: Iñaki Baz Castillo <ibc@aliax.net>
Date: Mon, 03 Dec 2018 22:26:17 +0100
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To: Sergio Garcia Murillo <sergio.garcia.murillo@gmail.com>
Cc: Magnus Westerlund <magnus.westerlund@ericsson.com>, rtcweb@ietf.org
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Archived-At: <https://mailarchive.ietf.org/arch/msg/rtcweb/vqmCzUq48-8CrhMgwhj326AlNPM>
Subject: Re: [rtcweb] Clarification on simulcast and RID and RepairedRtpStreamId
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On Mon, 3 Dec 2018 at 22:22, Sergio Garcia Murillo
<sergio.garcia.murillo@gmail.com> wrote:
> My point is that there is a single source in the transceiver/MID why
> should we add default RID and waste 2 more bytes in each media and rtx
> packet?

Regardless what browsers do today, both MID and RID headers should be
just included in the first packets. The receiver is supposed to update
its ssrc table for faster matching.

NOTE: The sender should also resend MID and RID if the SSRC changed
because some RFCs state that SSRCs may conflict and things that
absolutely never happen.

-- 
Iñaki Baz Castillo
<ibc@aliax.net>