Re: [splices] Using Two Separate Devices to Start a Conversation proposal

Alan Johnston <> Mon, 06 June 2011 21:45 UTC

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Date: Mon, 6 Jun 2011 16:45:40 -0500
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From: Alan Johnston <>
To: "Worley, Dale R (Dale)" <>
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Subject: Re: [splices] Using Two Separate Devices to Start a Conversation proposal
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But isn't the INVITE Join received at Alice's Desk Phone?  If so, then
a normal Join will result in Alice's Desk Phone performing mixing of
audio streams from Alice's PC, Alice's Desk Phone, and Bob.  I thought
what was desired (and shown by Rifaat's flow) was that Alice's Desk
phone did not mix the media, but instead inserted/spliced the media
from Alice's PC into the dialog with Bob, resulting in a re-INVITE to
Bob with two m= lines.

- Alan -

On Mon, Jun 6, 2011 at 4:15 PM, Worley, Dale R (Dale) <> wrote:
> No, surely it is an ordinary join.  At the far UA, there are two incoming dialogs, each with one audio m= line.  The only oddity is that one dialog is recvonly (at the far UA), and so is never sent media.  The other dialog is sendonly (at the far UA) and so never provides audio to the mixing, but is only sent the result of the mixing.  The effect is that the far UA's input audio is sent only to the second dialog, and the far UA's output audio is driven only by the first dialog.
> Dale