[MMUSIC] When a bundle offer is forked

Paul Kyzivat <pkyzivat@alum.mit.edu> Thu, 23 May 2013 17:46 UTC

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Date: Thu, 23 May 2013 13:34:04 -0400
From: Paul Kyzivat <pkyzivat@alum.mit.edu>
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To: Emil Ivov <emcho@jitsi.org>
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Cc: mmusic <mmusic@ietf.org>, Christer Holmberg <christer.holmberg@ericsson.com>
Subject: [MMUSIC] When a bundle offer is forked
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On 5/23/13 6:35 AM, Emil Ivov wrote:

> In case a bundle offer gets forked and various answers ...

I trimmed everything else out of Emil's reply, and changed to subject, 
because this is a whole different can of worms!

I think we must acknowledge that this *can* happen, though it is a low 
probability event. It raises all sorts of ugly issues. A few:

* if the bundle is accepted by multiple forks, does this form
   one RTP session or several? If so,

   - if so, then if each fork accepts a different set of m-lines from
     the bundle, how can that work with a single RTP session?

* How does ICE work in this case? (Is that already covered by ICE,
   since it mostly isn't specific to bundle?

* If one fork adds/removes an m-line from the bundle, should that
   be mirrored to the other forks?

* ...

ISTM that the simplest thing we could do about this is put a statement 
in the draft that this draft does not specify behavior in the case of 
forking - that conforming devices are constrained to a single fork, and 
that behavior in forking cases could be a subject of future standardization.