Re: [rtcweb] Proposal for dealing with CNAMEs and MSIDs for synchronization

"Cullen Jennings (fluffy)" <fluffy@cisco.com> Thu, 14 February 2013 20:36 UTC

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From: "Cullen Jennings (fluffy)" <fluffy@cisco.com>
To: Magnus Westerlund <magnus.westerlund@ericsson.com>
Thread-Topic: [rtcweb] Proposal for dealing with CNAMEs and MSIDs for synchronization
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Date: Thu, 14 Feb 2013 20:36:14 +0000
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Cc: "rtcweb@ietf.org" <rtcweb@ietf.org>
Subject: Re: [rtcweb] Proposal for dealing with CNAMEs and MSIDs for synchronization
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On Feb 14, 2013, at 2:17 AM, Magnus Westerlund <magnus.westerlund@ericsson.com> wrote:

> I think it is important that we are clear on that all media sources that
> comes from the same synchronization context must be using the same
> CNAME.
 
Agree - I might rephrase that slightly to change 

   	comes from the same synchronization context

to 
        come from the same synchronization context and that are desirable to synchronize 

The issues I am concurred with is a device that is producing both audio and video from a camera and some video from a slide share and may be capable of sending the two such that the receiver can synchronize them but that may not to syncronize them due to the additional latency that would impose on the audio. I want to be able to send the audio and video with same CNAME and the slides with a different CNAME. I was assuming I would do that by putting the Track with the slides in one RTCMediaStream and the other Tracks in a different RTCMediaStream. 

Perhaps the above wording is fine and we just need to be clear on what a  synchronization context is.