Re: [avtext] draft-avtext-berger-framemarking-00.txt

Colin Perkins <csp@csperkins.org> Thu, 26 March 2015 23:00 UTC

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From: Colin Perkins <csp@csperkins.org>
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Date: Thu, 26 Mar 2015 18:00:29 -0500
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Subject: Re: [avtext] draft-avtext-berger-framemarking-00.txt
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On 19 Nov 2013, at 16:21, Espen Berger (espeberg) <espeberg@cisco.com> wrote:
> The draft discuss usage of RTP header extension to do RTP simulcast operation on encrypted payload. 
> 
> Comments?  

To echo my comments in the working group session in Dallas:

- Given the goal of codec-agnostic processing, there seems to be considerable codec-specific information carried. I'd be more comfortable with this draft if the codec-specific information was left to payload headers, with only the codec-agnostic information (the first byte of the extension) being sent in a header extension.

- There's been some talk of potentially updating SRTP to better support private centralised conferencing. If that were done, it could potentially expose enough payload header information to support the use cases of this draft. It's not necessarily clear that this will happen, or is a good idea, but it should perhaps be considered. 

In general, though, I support this work.

Cheers,
Colin




-- 
Colin Perkins
https://csperkins.org/