[rtcweb] Back to the drawing board?

Henry Sinnreich <henry.sinnreich@gmail.com> Tue, 26 July 2011 01:40 UTC

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Date: Mon, 25 Jul 2011 20:40:48 -0500
From: Henry Sinnreich <henry.sinnreich@gmail.com>
To: Harald Alvestrand <harald@alvestrand.no>, rtcweb@ietf.org
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Subject: [rtcweb] Back to the drawing board?
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On Jul 25, 2011, at 8:06 AM, Harald Alvestrand wrote:

> An RTP session with both "audio" and "video" media types cannot be
> represented by an SDP description, since SDP ties RTP sessions 1-1 to the "m"
> line of the description, which contains the top-level type, and the codec
> descriptions omit the top-level type in their codec naming.
> 
> I've said elsewhere that I consider this to be a design mistake for entirely
> different reasons, but this debate has reinforced my opinion that it is.

This about sums it up why both SDP and RTP from VoIP of the early 1990's is
just not adequate. There are plenty of better solutions, such as metadata
standards for the app description data to replace stale SDP and app level
framing over UDP for RT media to replace RTP (a protocol build with media
mixing intermediaries/servers in mind).

Solutions without both SDP and RTP are widely deployed in dominant Internet
and Web RT communications products, albeit proprietary. And we want a
standard instead.

Avoiding telephony style VoIP and telecom multimedia usage scenarios and
their associated protocols is required to produce a successful standard for
webrtc, much preferable to the dominant proprietary products of today,
excellent as they may be.

Back to the drawing board?
It is not too late.

Thanks, Henry