Subject: Fwd: latest glossary

From: Abel Weinrib <[email-masked]>
Date: Wed, 7 Jul 1993 14:14:06 -0400 (EDT)

This document, prepared by Lakshman <[email-masked]> is a list of
terms and their definitions for the mmusic working group.  Many of the
definitions were extracted from other documents and from discussions
held during WG sessions.

The main naming dilemma centers around what to
call the user-and-media association; a conference, conversation, 
collaboration, session, aggregated session?!  Then, what to call a
media session: media session, transport session, data session, or
simply session?

Please comment with any strong preferences and/or opinions.  We plan to
discuss this document during the mmusic IETF sessions.

	 Glossary for Multiparty Multimedia Session Control WG
	 -----------------------------------------------------

Aggregated Session
	A logical abstraction that may consist of one or more related
	media sessions, among multiple in real time.

Aggregated Session Control 
	The management and coordination of multiple sessions,
	and their multiple users in multiple media.  The term
	session is used for shorthand.

Conference
	For the purposes of mmusic, a multiparty multimedia telemeeting;
	an aggregrated session.

Collaboration
	A more cooperative form of a conference.

Conference Scalability
	The ability of a conference to scale up in size.  Two metrics 
	of size include large numbers of remote participants and widely 
	dispersed participants.

Room-to-Room Conferencing
	Conferencing that involves groups of people convening in rooms, 
	then conferencing between rooms.

Desktop Conferencing
	Conferencing from one's desktop computer.  This has a personal
	and more spontaneous flavor than room-to-room conferencing.

Conference Session Manager
	An entity which resides at each user's end system to coordinate
	the orchestration, maintenance and interaction of sessions.  

Distributed Control
	A control model where control functions are distributed
	among conferees.

Centralized Control
	A control model where control functions are the responsibility
	of a centralized agent.

Tight-Control Session
	A session style in which state is actively shared
	among participants and that aims to keep state consistent among 
	participants.  

Loose-Control Session
	A session style in which state information is passively shared
	among participants.  In the extreme, no state sharing is performed.
 
Media Agent
	An entity that handles media-specific functions such
	as encoding, compression and transport packetization
	that are associated with a session.
	Media in conferences might include audio, video, graphics or 
	text.

Media Session
	A transport session (point-to-point or multipoint) in a single 
	medium.

Media Configuration Management
	The management of media descriptions, including
	the static end-system descriptions (hardware and software 
	capabilities), as well as the negotiated
	per-session preferences.

Conferee
	A party involved in a conference.  An endpoint for session control
	communication.

Initiator
	A participant who initiates a conference.

Chair
	A participant who is designated as having more authority than
	other members of the conference.  For example, the chair might 
	decide the policy on late joins, media floor control, 
	interaction style, etc.

Receiver
	A conferee who receives session data. 

Sender
	A conferee who transmits/sends session data.

Passive Participant
	A conferee who only acts as a receiver.

Active Participant
	A conferee who acts both as a sender and receiver.

Session Relay
	An entity that relays data between participants, by acting
	as a go-between. 

Floor Control
	Coordinated control over who may or may not send and/or receive data.

Connectivity Style
	The interconnectivity of conferees (e.g., 1-to-N, N-to-N,
	M-to-N) in either the control or data realm.

Access Control
	The accessibility of a session to potential participants.
	
Conference Directory Service
	A directory that provides user network addresses, conference
	IDs and addresses, the conference begin time, conference topic,
	etc.

Conference Scheduling
	The advertisement of a conference's start time with a session 
	directory service.

Interaction Policies
	The model and rules used by participants to interact with one 
	another in a conference.

---

From: Fengmin Gong <[email-masked]>
Date: Wed, 7 Jul 1993 23:29:24 -0400 (EDT)

I would very much like to come to the WG meeting for discussion but...
Here are some of my comments.  I will be tuning in to Channel 2 then.

Fengmin

>	 Glossary for Multiparty Multimedia Session Control WG
I think these two dimensions are definitely very appropriate for scalability.
But I also feel scalability in conferencing quality (e.g., video quality)
with available network BW etc is also an important property of a "conference
system", maybe it should be part of conference scalability here.

>	the orchestration, maintenance and interaction of sessions.  

Aggregated session was defined earlier but not conference session.  I
assume conference session=aggregated session=conference=session(for short), 
if so we need to make it explicit in the glossary.

>	A control model where control functions are distributed

Conferees and conference site may not have a 1-1 relationship in the
case of a room-to-room conference, do we want to use conference site
here instead of conferee?

>	A party involved in a conference.  An endpoint for session control
It seems more consistent with traditional conference concept to interpret
a conferee as individual participants, but this interepretation will
not be consistent with the interpretation as an endpoint for session
control communiation.  I prefer the individual interpretation and then
define an endpoint to be a conference site (typically associated with
the machine where session control agent resides).

>	A conferee who transmits/sends session data.
Similarly, conference site seems to be a more approapriate term than conferee.
According to early definition, an unqualified "session" means an aggregated
session, then this receiver and sender definition fails to differentiate,
e.g., between a site that only receives video but sends and receives audio, and
a site that only receives audio and video.  It seems that receiver and sender
need to be explicit  with media.

>	An entity that relays data between participants, by acting
Should session relay be also media bound?

>	IDs and addresses, the conference begin time, conference topic,

and media encodings used.

>	The model and rules used by participants to interact with one 

Cheers!