Re: [AVTCORE] update to RFC5285

Colin Perkins <csp@csperkins.org> Wed, 30 September 2015 10:31 UTC

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From: Colin Perkins <csp@csperkins.org>
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Date: Wed, 30 Sep 2015 11:31:09 +0100
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Subject: Re: [AVTCORE] update to RFC5285
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Hi Roni,

> On 29 Sep 2015, at 20:58, Roni Even <ron.even.tlv@gmail.com> wrote:
> 
> Hi,
> http://tools.ietf.org/id/draft-even-avtcore-rfc5285-bis-00.txt   updates RFC5285 allowing mixing one byte and two bytes RTP header extensions in the same RTP stream. This mode is negotiated using a new SDP attribute.

This looks good, but I had a couple of quick comments:

- Section 4.1 changes “MUST NOT be mixed” to “MAY be mixed”, but that’s inconsistent with Section 6. I think Section 4.1 ought to say “MUST NOT be mixed unless support for mixing one- and two-byte header extensions is signalled as in Section 6”. 

- The draft needs to define the ABNF for the new “mix-headers” SDP attribute. I also suggest “a=extmap-allow-mixed” might be a more consistent name than “a=mixed-headers”.

- The draft removes the description of how IANA should manage the namespace, and the initial registrations. I don’t think this should be removed, but if it is, the IANA considerations needs an additional paragraph stating that the IANA registry for RTP Compact Header Extensions is to be managed in accordance with RFC 5285.

Cheers,
Colin




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