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Re: Re: Re: New Version Notification for draft-guduru-rtcweb-codec-preferences-01.txt

From: Justin Uberti <juberti@google.com>
Date: Tue, 22 Jul 2014 23:42:32 -0400
Message-ID: <CAOJ7v-3O_0V-LUGkH2+KL=-HjqRH-oi1We8S5cJFVWkaWEntWg@mail.gmail.com>
To: Kiran Kumar Guduru <kiran.guduru@samsung.com>
Cc: franklin blek <franklin.blek@gmail.com>, "public-webrtc@w3.org" <public-webrtc@w3.org>, "rtcweb@ietf.org" <rtcweb@ietf.org>
> This is a useful example, thanks for explaining this. But I think this is
> the wrong solution. Quoth RFC3264, S. 7:
> *   When the offerer receives the answer, it MAY send media on the*
> *   accepted stream(s) (assuming it is listed as sendrecv or recvonly in*
> *   the answer).  It MUST send using a media format listed in the answer,*
> *   and it SHOULD use the first media format listed in the answer when it*
> *   does send.*
>  Note the use of SHOULD vs MUST.
>  [KIRAN] section 7 explains about "offerer processing of the Answer". But
> I think the correct section for my explanation is section 6, " Generating
> the Answer", which recommonds to use the same order of preference as that
> in the offer.
>    "Although the answerer MAY list the formats in their desired order of
>    preference, it is RECOMMENDED that unless there is a specific reason,
>    the answerer list formats in the same relative order they were
>    present in the offer."
The text says "unless there is a specific reason". You have a specific
reason. Just do it.

It is far more sensible to change the order of codecs in the answer, than
to send a reoffer with changed codecs immediately afterwards.
Received on Wednesday, 23 July 2014 03:43:19 UTC

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