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Re: [rtcweb] Question about JSEP createOffer

Justin Uberti <juberti@google.com> Tue, 08 May 2012 14:46 UTC

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From: Justin Uberti <juberti@google.com>
Date: Tue, 08 May 2012 10:46:32 -0400
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To: "Ejzak, Richard P (Richard)" <richard.ejzak@alcatel-lucent.com>
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Cc: "rtcweb@ietf.org" <rtcweb@ietf.org>
Subject: Re: [rtcweb] Question about JSEP createOffer
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Richard,

That is an interesting point. Could you give a short example of when such a
"full" re-OFFER would be used? There are a few ways we could handle this
case.

On Sun, May 6, 2012 at 2:40 PM, Ejzak, Richard P (Richard) <
richard.ejzak@alcatel-lucent.com> wrote:

>  I have a question about something I came across in the JSEP draft.****
>
> ** **
>
> 6.1.2 of JSEP draft 0 has the following text regarding “createOffer”:****
>
> ** **
>
>    As an offer, the generated SDP will contain the full set of****
>
>    capabilities supported by the session (as opposed to an answer, which**
> **
>
>    will include only a specific negotiated subset to use); for each SDP***
> *
>
>    line, the generation of the SDP must follow the appropriate process****
>
>    for generating an offer. In the event createOffer is called after the**
> **
>
>    session is established, createOffer will generate an offer that is****
>
>    compatible with the current session, incorporating any changes that****
>
>    have been made to the session since the last complete offer-answer****
>
>    exchange, such as addition or removal of streams. If no changes have***
> *
>
>    been made, the offer will be identical to the current local****
>
>    description.****
>
> ** **
>
> The first and last sentences might conflict if the SDP Answerer later
> wants to create a new Offer.  The local configuration based on the first
> offer/answer will contain only the selected media configuration, whereas it
> is desirable for the new Offer to contain the full set of capabilities of
> the (new) Offerer.  I think this text needs to change to reflect this case.
>  Am I missing something?****
>
> ** **
>
> Richard****
>
> _______________________________________________
> rtcweb mailing list
> rtcweb@ietf.org
> https://www.ietf.org/mailman/listinfo/rtcweb
>
>

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