Subject: [dispatch] Milestone(s) for the Sound Level Indicators problem

From: Enrico Marocco <[email-masked]>
Date: Mon, 8 Jun 2009 21:33:46 +0200

After some online and offline discussion about how to address the
problem described in draft-ivov-dispatch-slic-ps-00, i.e. how to enable
a mixer to pass the sound levels of the contributing streams that result
in a mixed stream back to the clients, it seems that a reasonable way
forward would be to have the AVT WG defining the missing piece (an RTP
extension to encode sound level values for the CSRCs). So, we would like
to propose the following milestone for AVT:

"Submit RTP header extension (as per RFC 5285) for multiple sound level
indicators."

For whoever has missed it, the problem was initially discussed here:
http://www.ietf.org/mail-archive/web/dispatch/current/msg00071.html

As usual, comments are welcome.

-- 
Ciao,
Enrico

---

From: Roni Even <[email-masked]>
Date: Tue, 09 Jun 2009 00:28:05 +0300

Enrico
I read draft-ivov-dispatch-slic-ps-00 and what is still bothering me is that
since you do not want to use the conference event package to map between the
ssrc and the display name for the user (like Bob, Alice), I am not sure how
this will work. The mixer will just give the SSRCs of each original stream.
It can not supply the mapping since the mixer is not supposed to know it.

Are you going to address this part or will it be left to each specific
implementation and is out of scope to this work. I am not sure that the
client can do it by itself without any information from a central entity.

Roni Even

-----Original Message-----
From: [email-masked] [mailto:[email-masked]] On Behalf
Of Enrico Marocco
Sent: Monday, June 08, 2009 10:34 PM
To: [email-masked]
Subject: [dispatch] Milestone(s) for the Sound Level Indicators problem

After some online and offline discussion about how to address the problem
described in draft-ivov-dispatch-slic-ps-00, i.e. how to enable a mixer to
pass the sound levels of the contributing streams that result in a mixed
stream back to the clients, it seems that a reasonable way forward would be
to have the AVT WG defining the missing piece (an RTP extension to encode
sound level values for the CSRCs). So, we would like to propose the
following milestone for AVT:

--
Ciao,
Enrico

---

From: Emil Ivov <[email-masked]>
Date: Tue, 09 Jun 2009 02:22:22 +0200

Hey Roni,

We definitely want to use the conference package for the mapping.
There's absolutely no doubt about this. I believe we mention it once or
twice in the draft but probably not clearly enough. Apologies.

What we don't want to do is use the mechanisms in the conference package
to transport the sound level information itself. In other words we want
the actual sound levels in RTP packets and not in SIP messages.

Hope this makes it clearer.

Emil

Roni Even wrote:
> _______________________________________________
> dispatch mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/dispatch
> 

-- 
Emil Ivov, Ph.D.                               30a rue de la Patrie
Project Lead                                   67300 Schiltigheim, France
SIP Communicator
[email-masked]                     FAX:   +33.1.77.62.47.31
http://sip-communicator.org                    PHONE: +33.1.77.62.43.30

---

From: Roni Even <[email-masked]>
Date: Tue, 09 Jun 2009 08:20:10 +0300

Emil,
Sorry if I did not understand but the draft mentions that SIP based solution
like conference event package will not work in XMPP environment (section 2.1
of the draft)

" It is probably also worth mentioning that the use of RFC 4575
   [RFC4575] for such a feature would make the mechanism incompatible
   with non-SIP signaling protocols like, for example, XMPP [RFC3920]
   and its Jingle extensions."

Roni

-----Original Message-----
From: [email-masked] [mailto:[email-masked]] On Behalf
Of Emil Ivov
Sent: Tuesday, June 09, 2009 3:22 AM
To: Roni Even
Cc: [email-masked]
Subject: Re: [dispatch] Milestone(s) for the Sound Level Indicators problem

Hey Roni,

Emil

---

From: Emil Ivov <[email-masked]>
Date: Tue, 09 Jun 2009 09:38:42 +0200

Hey Roni,

>    and its Jingle extensions."

Yes and again, this is about using 4575 to _transport_ the sound levels.

We'll soon submit a draft proposing a possible solution. It will be
explaining our approach in more detail and would hopefully clarify
issues that were left unclear by the problem statement.

Cheers
Emil

---

From: "Mary Barnes" <[email-masked]>
Date: Thu, 11 Jun 2009 08:44:19 -0500

Hi folks,

The DISPATCH WG chairs have asked the ADs to move this work item to the
AVT WG.  Obviously, the work begins with an individual document in the
AVT WG and the ongoing discussion in that context would be entirely on
the AVT WG mailing list.  

Thanks,
Mary. 

-----Original Message-----
From: [email-masked] [mailto:[email-masked]] On
Behalf Of Enrico Marocco
Sent: Monday, June 08, 2009 2:34 PM
To: [email-masked]
Subject: [dispatch] Milestone(s) for the Sound Level Indicators problem

--
Ciao,
Enrico

---

From: Enrico Marocco <[email-masked]>
Date: Thu, 11 Jun 2009 16:00:58 +0200

Thanks Mary, we are about to submit a new draft in AVT and will try to
move the work forward there.

As an unasked, gratuitous comment, I would like to say that we have
quite appreciated the new process: in our particular case, a few weeks
of discussion in DISPATCH have probably saved several iterations in
different WGs.

Enrico