Subject: Opinions Requested

From: [email-masked]
Date: Mon, 20 Feb 1995 20:01:46 +0000 (GMT)

Hi,

I am a student working towards a Ph.D. and have been looking at video
mediated communication and the session control protocols required to
support them.

One area we are particularly interested in is informal group work,
that is supporting the kind of working environment one would find in
an an open plan office (often referred to as a mediaspace
eg. Xerox). We have been looking at the characteristics that we think
a session control protocol would need to have in order to support such
a 'conference' environment.

We feel that,

 - There will be two primary aspects to the Session model,

	* A long lived 'Awareness Group' - for the propagation of
awareness based information such as snapshots.

	* Short lived 'Focused' Interactions - Audio/Video connections
with particular emaphsis on non-intrusive 'glance', point to point/n-way
videophones.

 - The workgroup would be long lived; A group would be created
(possibly statically) for propagation of 'awareness' type data
eg. video snapshot every 20 mins. Also membership of the group would
implicitly mean that one would accept 'focused' connections (eg videophones)
from other members of the group (without a request - accept call
setup).

- The 'focused' internal group connections such as point-point
audio/video connection need to have fast set up and tear down times to
support the informal communication model, these connections will often
be of a short duration but maybe repeated many times during a
day. Also the membership model for this interaction is implicitly
accepted (since this member belongs to the awareness group)

 - Scaleabilty is not an issue (the work group would be organization
based with maybe 10's of members) 

This seems to motivate a loose control model for the awareness based
state, while the focused interaction would require a more tightly
controlled state model. What we have in mind is a fairly lightweight
session service that aims to support some of the characteristics
identified by sociological research into informal workgroups. Currently
the protocol and session service exists as a paper design only.

I guess the question I am asking is whether people think that this is
a reasonably valid idea for a session protocol, and whether it will be
significantly different from what can be achieved with other protocols
currently being developed (I have read most of the session control
related papers from the confcntrl archives). (eg. could informal
workgroups be supported with a more generic protocol and simply by
applying a policy).

I would really welcome some feedback on this, particularly opinions on
how valid people think a more lightweight session service aiming to
support informal workgroups is, or any advice.

Cheers,

Alastair.

ps. if any of this is unclear I'll be happy to try and clarify it.

--
Alastair Harris                         Internet : [email-masked]
Computer Science Dept.                  Telephone: +44 71-975 5220
Queen Mary & Westfield College,              
University of London, Mile End Road,    LONDON. E1 4NS, UK.