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

Eric Rescorla <ekr@rtfm.com> Thu, 07 February 2013 20:04 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Thu, 07 Feb 2013 12:03:22 -0800
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To: Stefan Hakansson LK <stefan.lk.hakansson@ericsson.com>
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Subject: Re: [rtcweb] Proposal for dealing with CNAMEs and MSIDs for synchronization
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On Thu, Feb 7, 2013 at 11:59 AM, Stefan Hakansson LK <
stefan.lk.hakansson@ericsson.com> wrote:

> On 02/07/2013 08:43 PM, Eric Rescorla wrote:
>
>>
>>
>>
>
>>     My question is basically: what if the sender creates two
>>     MediaStreams for which all tracks have local sources (cam's,
>>     mike's), sends them to a peer, will the RTP streams for both
>>     MediaStreams have the same or different CNAME?
>>
>>     I argued for that they should have the same.
>>
>>
>> Yes, I think this is a separate (and fraught) question. :)
>>
>
> Separate question, but I think the answer should be documented (regardless
> on if it is "same", "different" or "implementers choice").
>

Agreed.

-Ekr


>
>> -Ekr
>>
>>
>>         4. There are two ways for MSID and CNAME to be inconsistent.
>>         - If MSID indicates synchronization but different CNAMEs are
>>         provided,
>>             synchronization is not attempted.
>>         - If MSID indicates no synchronization but the same CNAME is used,
>>             then the tracks shall be synchronized, even though they
>>         appear in
>>             different MediaStreams.
>>
>>         -Ekr
>>
>>
>>
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>