Subject: Session Description Protocol pre-draft (1.4)

From: Mark Handley <[email-masked]>
Date: Wed, 12 Jul 95 15:22:18 +0100

Unfortunately I missed the I-D deadline for the Stockholm IETF (spent
too much time re-configuring the European Mbone in time for the IETF!)

There is a new SDP draft, but as I've already missed the deadline, I
thought I'd just release it to confctrl and remconf for now, and then
amend it and release it properly after the IETF along with a draft
desribing the announcement protocol, which has now been removed from
the SDP draft.

Quite a bit has changed - though almost all of the changes have been
discussed either in Danvers or on the confctrl list.

You can get a copy from:
http://www.cs.ucl.ac.uk/staff/M.Handley/sdp.01.ps

Mark

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From: Ruth Lang <[email-masked]>
Date: Thu, 13 Jul 1995 18:22:17 -0700

Mark,

>>How would I go about describing a group of non-multicast multi-user
>>applications which use a) the same port across the group of
>>participants, b) different ports (i.e., host, port pair is unique per
>>participant)?
> 
> This depends so much on the distribution mechanism, but lets assume
> for a second you dont multicast announce a unicast conference.  If you
> unicast the SDP messages to each participant (using HTTP or whatever),
> you can have a unique SDP message per participant.  Each c field gives
> the address of the mixer or whatever it is the participant should
> contact.

If the participants do not contact a single source or mixer but need
to contact each other (i.e., be fully connected), then a single SDP
message to each is not sufficient.  A list is required somewhere to
provide that information (or am I somehow missing your point about
separate announcements?).

Ruth