Re: [MMUSIC] draft-holmberg-mmusic-t140-usage-data-channel - multi-party

Paul Kyzivat <pkyzivat@alum.mit.edu> Tue, 27 August 2019 18:39 UTC

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From: Paul Kyzivat <pkyzivat@alum.mit.edu>
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Date: Tue, 27 Aug 2019 14:39:49 -0400
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Subject: Re: [MMUSIC] draft-holmberg-mmusic-t140-usage-data-channel - multi-party
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On 8/26/19 3:59 PM, Gunnar Hellström wrote:

> 4. A multi-party server S, combining a number of sources into one call 
> to a participant A, with real-time text from each other participant 
> (B,C,...) communicated in just one T140 data channel between S and A.  
> There is a need to indicate source for each T140block sent to A. We 
> currently have no way specified for that. An extension of T.140 could do it.

Is there a reason to ever do this?

In audio and video the "mixing" actually does something irreversible. 
And it takes real work to do it, and doing so reduces the bandwith 
considerably over what is required to transmit the individual streams.

For RTT none of that is true. There is very little impact in bandwidth 
or processing in transmitting them all as separate channels.

So why not just say "don't do that"?

	Thanks,
	Paul