Re: [dcon] DCON and Media

Alan Johnston <alan.b.johnston@gmail.com> Mon, 14 November 2011 01:37 UTC

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Date: Sun, 13 Nov 2011 19:37:02 -0600
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From: Alan Johnston <alan.b.johnston@gmail.com>
To: Lorenzo Miniero <lorenzo@meetecho.com>
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Subject: Re: [dcon] DCON and Media
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Lorenzo,

Great.  So media mixing is not completely out of scope, but we will
initially only work on the simple cascaded media mixing.

For the future, it might be useful to do this work in stages.  For example:

1. First define simple cascaded media
2. Next, provide ability for a DCON entity to discover the media graph
3. Then define a mechanism for a participant to leave and join the
conference for the purpose of changing their location in the media
graph.  This would prevent having to propagate state changes that the
participant has left the conference, then the participant has joined
the conference when they are just changing their point of attachment.
4. Then provide a way for a DCON entity to request media graph changes
in another DCON entity.

Perhaps we decide to only do 1 and 2, or just 1 in the first round of DCON work.

- Alan -

On Fri, Nov 11, 2011 at 1:23 PM, Lorenzo Miniero <lorenzo@meetecho.com> wrote:
> Hi Alan,
>
>
> On Thu, 10 Nov 2011 11:50:54 -0600
> Alan Johnston <alan.b.johnston@gmail.com> wrote:
>
>> I am greatly looking forward to getting started on the DCON work.  Thanks to everyone who has worked on the comprehensive set of drafts.
>>
>> I have one high level question about the work. Having read the DCON framework and requirements drafts, I understand how state will be shared among the distributed elements. However, I am not clear on the media sharing which needs to happen for any DCON conference.
>>
>> In a few places, the drafts say media mixing is out of scope, but we do need to define how it will work in the simple cascaded case, right?  I can see how mixing optimization could be deferred for later.
>>
>
>
> Absolutely! Cascaded conferencing is the starting point, especially in terms of mixing, and I agree we'll need to at least say a few words about how it will be supposed to work. Things start to get complicated, though, when involving advanced stuff like distributed video mixing, for instance, and that's what we thought would be out of scope when writing the drafts.
>
> Lorenzo
>
>
>> - Alan -
>>
>>
>> _______________________________________________
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>
> --
> Lorenzo Miniero, COB
>
> Meetecho s.r.l.
> Web Conferencing and Collaboration Tools
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