[rtcweb] About unified Plan and multiple m lines

Iñaki Baz Castillo <ibc@aliax.net> Wed, 24 July 2013 14:09 UTC

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From: Iñaki Baz Castillo <ibc@aliax.net>
Date: Wed, 24 Jul 2013 16:08:17 +0200
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Subject: [rtcweb] About unified Plan and multiple m lines
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Hi, let's suppose WebRTC 1.0 borns with "Unified Plan" built-in, and
my browser receives a session invitation from a conference server, and
there are 8 audio participants in the conference.

So the SDP I receive has 8 "m=audio" lines, maybe with different audio
codecs in each line. And following SDP O/A rules my browser will
generate SDP answer that will also contain 8 "m=audio" lines.

Now, where it is supposed my browser will send my single audio track
to the conference server? What does it mean that I receive 8 "m=audio"
lines while I'm just able to send a single audio track? which m=audio
line should I use for sending RTP?

Thanks a lot.

Iñaki Baz Castillo