Subject: [MMUSIC] Questions about ICE candidates with BUNDLE
From: Peter Thatcher <[email-masked]>
To: "[email-masked]" <[email-masked]>
Date: Thu, 12 Nov 2015 12:36:25 -0800
List-Id: Multiparty Multimedia Session Control Working Group <mmusic.ietf.org>

While implementing BUNDLE, we ran into a few questions
about draft-ietf-mmusic-sdp-bundle-negotiation-23, especially section 11
and when ICE candidates are included in m-lines:

1.  It says "answerer MUST assign shared ICE candidates to each bundled
'm=' line ... in the answer".  What is the reasoning for duplicating
candidates in this way in the answer?  Clearly at this point, the offerer
understands BUNDLE and BUNDLE is negotiated, and the offerer (when using
bundle-only) doesn't include duplicate candidates, so what's value in
duplicating the candidates in the answer?  If there isn't a good reason,
I'd prefer to not duplicate them, even if that means using 'a=bundle-only'
in the answer (which is currently unspecified)

2.  If the answerer does not include any candidates in the answer and
instead trickles them later, should it trickle them N times (once for each
m-line in the BUNDLE group) or 1 time?  1 time seems much more reasonable
than N times, but if we duplicate candidates in the answer, but not
duplicate them while trickling, that's a bit inconsistent.  Yet another
reason to not duplicate in the answer :).

3. (more for editors)  Everything refers to "11.1", but 11.1 doesn't say
much.  Does it mean "11.2.1", which has more substance?

4. (more for editors) 11.2.2 and 11.2.5 are exactly the same.  Why not just
remove 11.2.5 and say 11.2.2 refers to all offers?

Thanks,
Peter