Subject: Re: [rmcat] draft-alvestrand-rmcat-remb

From: Harald Alvestrand <[email-masked]>
Date: Sun, 03 Feb 2013 00:41:43 +0100

On 01/28/2013 07:25 PM, Hassnaa Moustafa wrote:
> Hi,
> After reading the draft on (RTCP message for Receiver Estimated 
> Maximum Bit Rate "draft-alvestrand-rmcat-remb"), it's not clear for me 
> what is the target/scope of  "multiple media streams" mentioned in the 
> draft, is there a specific use-case fpr that "for example video 
> conferences with more than one stream")?
Thanks for the question!

All videoconferencing applications use at least one video stream and one 
audio stream from the participant to the mixer (there might be more 
video streams, data streams or other streams too).

Some use more. For instance, Google Hangouts uses one video stream and 
one audio stream per participant from the mixer to the participants.

It would be strange indeed to insist that each of those streams should 
be considered a separate congestion control regime.

> Regards,
> Hassnaa

---

From: Matt Mathis <[email-masked]>
Date: Sun, 3 Feb 2013 16:09:35 -0800

On Sat, Feb 2, 2013 at 3:41 PM, Harald Alvestrand <[email-masked]>wrote:

> It would be strange indeed to insist that each of those streams should be
> considered a separate congestion control regime.

It would be strange indeed to insist that each of those streams should be
considered a single congestion control regime.

If the bridge is transcoding, and everybody has their own local bottleneck,
then you want everybody to have their own congestion control regime.
If the bridge can not transcode, and especially if there might be
congestion local to the bridge, then clearly the system will be better
behaved if they share a common congestion control regime.

The point is the architecture has to support both.

Thanks,
--MM--
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