Re: [maitai] Roles of Sender and Receiver

"Mike Hammer (hmmr)" <hmmr@cisco.com> Thu, 02 December 2010 19:46 UTC

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From: "Mike Hammer (hmmr)" <hmmr@cisco.com>
To: Peter Musgrave <peter.musgrave@magorcorp.com>, "Charles Eckel (eckelcu)" <eckelcu@cisco.com>
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Subject: Re: [maitai] Roles of Sender and Receiver
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Ummmm....

Part of the issue is that with multiple participants with multiple
inputs and outputs, you can't send all inputs from all sites to all
other sites.  You kill the network, so some judicious control of what is
sent when and to whom is needed.  That means that some inputs
(microphone or camera) are not transmitted at times.

So, do we allow legs to be asymmetric or not?

Interested in your view of the collective impact of these types of
control decisions.

Mike


-----Original Message-----
From: Peter Musgrave [mailto:peter.musgrave@magorcorp.com] 
Sent: Thursday, December 02, 2010 2:00 PM
To: Charles Eckel (eckelcu)
Cc: Mike Hammer (hmmr); maitai@ietf.org
Subject: Re: [maitai] Roles of Sender and Receiver


On 2010-12-02, at 11:10 AM, Charles Eckel (eckelcu) wrote:

>  have 3 cameras, left, center, and right.
> I can provide these as:
> - 3 separate streams
> - 1 active speaker switched stream
> - 1 stream composed of the three

Ok, I see what you're after. 

In the case where the receiver elects to get three separate streams,
then I have a refinement for my question. 

Who now decides how the streams from A map on to screens at B?

A could send streams targeted at specific screens at B (after examining
B's description of it's screens)

-or-

B could send A instructions on where to send each stream (based on
examining A's description of it's cameras)

-or-

We can find use-cases in which both techniques might be required. 

I am trying to decide how complete the information in a room description
really needs to be. While I like the idea of a reasonably complete
physical description (since it is very future proof) - I think it
imposes a burden on each side which might not be warranted. The other
extreme (just label cameras left, center, right) seems to obviously
limited. Where is the middle ground?

Peter Musgrave