Re: [rtcweb] To multiplex or not!

Stefan Håkansson LK <stefan.lk.hakansson@ericsson.com> Wed, 20 July 2011 06:36 UTC

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Date: Wed, 20 Jul 2011 08:36:00 +0200
From: Stefan Håkansson LK <stefan.lk.hakansson@ericsson.com>
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Subject: Re: [rtcweb] To multiplex or not!
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On 2011-07-19 18:40, Matthew Kaufman wrote:
> On 7/19/2011 7:28 AM, Magnus Westerlund wrote:
>> a) MUST be sent as Individual flows for each component.
>>
>> b) MUST be multiplexed into a single transport flow.
>>
>> c) SHOULD be multiplexed into a single transport flow, but the RTCWEB
>> peer MUST be able to send them as individual flows.
>>
>> I would love if people can indicate their choice or preferences.
>
> C. But I'm not sure that the "must" needs to be anything more than "you
> just make two peer connection objects, one for each". (In other words,
> any API that allows for multiplexing almost certainly allows for
> non-multiplexing)... this assumes that the multiplexing is implicit, of
> course. With explicit multiplexing it is even harder... the API needs to
> support turning on and off the multiplexing shim as well, something I'm
> not in favor of.
The APIs being discussed now deal with "MediaStreams" that contain both 
audio (zero to many) and video (zero to many). This has been found to be 
a reasonable level of abstraction for the web app developer. The web app 
developer would have difficulties to understand how many RTP streams a 
MediaStream would generate. So it is not so simple to deal with this by 
creating several peer conn objects.

Besides, it has been discussed that A/V synch should be maintained 
within a MediaStream. This is something you would lose if you split it 
up and transport it using separate peer conn objects.

Stefan
>
> Matthew Kaufman
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