Subject: [MMUSIC] Floor-media stream mappings

From: Gonzalo Camarillo <[email-masked]>
Date: Tue, 28 Dec 2004 20:00:15 +0200

Folks,

I am working on a new version of the draft below, which will be an 
MMUSIC WG item as agreed in our last meeting in DC.

http://www.ietf.org/internet-drafts/draft-camarillo-mmusic-sdp-bfcp-00.txt

We need a means to provide clients with the Floor IDs to be used in the 
conference and with the mapping of  each Floor ID with one or more media 
streams. For example, floor ID 123 maps to the media stream whose media 
label is 456.

a=floorid:123 m-stream:456

We would like to get feedback on a couple of issues:

1) Do we want to include human readable information about the floors 
encoded in the SDP? (e.g., "request this floor if you want to make a 
comment on the issue being discussed" or "request this floor if you want 
to bring up a new issue to be discussed")

2) Do we want to allow the syntax of the 'floorid' attribute to express 
Floor IDs that do not map to any media stream? If the answer to both 1) 
and 2) is yes, we could use the floor control protocol to moderate 
face-to-face meetings where the media does not traverse any mixer, for 
example.

Of course, both 1) and 2) are interesting features that will probably 
need to be supported by the conference policy. The question here is 
whether or not we want systems using solely SDP to have access to these 
features.

Thanks,

Gonzalo

_______________________________________________
mmusic mailing list
[email-masked]
https://www1.ietf.org/mailman/listinfo/mmusic

---

From: Cullen Jennings <[email-masked]>
Date: Wed, 29 Dec 2004 13:52:33 -0700

> a=floorid:123 m-stream:456

Just to make sure I understand - I assume that several floors could map to
one media stream and a single floor could also map to multiple media stream
(like audio and video).

> to bring up a new issue to be discussed")

no - the human language issues make me not want to do this. I'm fine with a
a convention that if their is a floor, you probably need to request it if
you want anyone to pay intention to your media. Clearly your second example
would not follow this but I think there are many ways other that SDP that
users could get the idea of what to floor was used for. I don't find these
human readable things in SDP very useful in practice.

That said, I don't feel strongly about this - it the human readable
description is never used, it does no harm. It could also be added later if
it was needed. 

> face-to-face meetings where the media does not traverse any mixer, for

yes 

And would also like to consider being able to specify a floor id when no
media stream exists but where the media stream and association to floor will
be added in a future SDP. It may be the requesting of the floor that causes
the creation of the media stream.