Re: [rtcweb] Changing video size (Re: use case:)

Stefan Håkansson LK <stefan.lk.hakansson@ericsson.com> Tue, 21 June 2011 15:36 UTC

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Date: Tue, 21 Jun 2011 17:35:54 +0200
From: Stefan Håkansson LK <stefan.lk.hakansson@ericsson.com>
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Subject: Re: [rtcweb] Changing video size (Re: use case:)
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+1
On 2011-06-21 17:26, Harald Alvestrand wrote:
> On 06/21/11 09:45, Varun Singh wrote:
>> In case of RTP, RTCP carries network level reception statistics and video/voice metrics (RTCP XR etc). However, there is a no standardized congestion control for RTP (http://tools.ietf.org/html/draft-gharai-avtcore-rtp-tfrc-00 uses packet loss and delay not some of the other cues mentioned in the mail).
>>
>> Unless we identify a congestion control, I would suggest that the use-case capture that we need an extensible mechanism to carry this type of information and then the sender implements its own congestion control (best to its ability).
>>
> I think we need to separate the two requirements:
>
> - response to network conditions (congestion control)
> - response to recipient system conditions such as window size, CPU load,
> window being obscured, and so on.
>
> Even though the possible actions to take might be the same, the two are
> fundamentally different; responses to end system events concern only the
> sender and the recipient, while responses to congestion events have the
> requirement that the behavior be globally sensible - that is, works well
> with the algorithms deployed by other users of the network.
>
>                            Harald
>
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