[AG-TECH] Persistent space? AND Hi res video streams

Craig Locatis LocatiC at mail.nlm.nih.gov
Thu Mar 13 14:21:08 CST 2003

An interesting article/study about this that predated networked videoconferencing was done at Xerox PARC that might interest you where they had cohorts constanty connected via video at distant offices.  See "Media space and Communicative Asymmetries: Preliminary Observations of Video-Mediated Interaction" by Heath and Luff, Human Computer Interaction, 1992, V 7, n 3, pp 315-346.  An abstract can be found at this link:


I share this interest, but I'm a novice to the AG who's still trying learn and get our node to behave consistently.


>>> Gurcharan S. Khanna <Gurcharan.S.Khanna at dartmouth.edu> 03/12/03 11:24PM >>>
hi tom and wenjun,

i am extremely interested in these issues and have been trying to
move in these directions but there is a lot of resistance and obstacles.

as tom mentioned, getting dedicated space is not easy. a multipurpose
room, as our node is, is not easily seen as a persistent space, since it
has to be turned on and off. however, other kinds of spaces are possible,
thoug spaces, but have encountered various kinds of resistance (social,
economic). i think, however, that these public spaces would be used as
informal, serendipitious connections to other public spaces with similar
users (e.g, students to students). I am trying to set this up between
campus points and then hopefully, between campuses of different schools.

the other kind of space is more personal, the desktop, or can be. to this
end i have tried to setup an always on type of venue for like-minded users,
specifically, those interested in digital video and also those who manage
research computing organizations. while i have found interest in this, so
far few have had the time to actually take the necessary steps to set
this up, even though it's not much (a PIG would be sufficient). i think for my
part, having a "lobby" of my colleagues always being there (potentially)
would be a great way for me to brainstorm, get a reality check, etc. a
consideration however is that it has to be fairly small and intimate. i
can't really relate to a hundred strangers but i can develop a  relationship
with 6 or 12 or even maybe a pool or 20 people that i get to know. so,
there has to be a fairly tight, cohesive, purpose to the group.

so far, i have had one colleague that shares this concept with me and we
have shared a common venue for several months. our connection is always
on, audio listening is always on, so we can attract each other's attention
when desired. often, days might go by with no interaction except we see
each other informally any time we're at our desks. when we do talk, it's
friendly, casual, and professional depending on the situation. i'd like to
extend this to a slightly larger group but it does take a certain acceptance
(trust? comfort?).

an independent but important factor is quality. while current AG video
quality is usable, i think that more realistic video would make this concept
more attractive, especially in public venues, where the image really has
to be life sized and of the highest quality. i'm currently experimenting with
streaming DV video (working out the multicast and bandwidth hogging issues--it
uses about 30Mbps per video stream) and it certainly has high impact on those
who see it next to H.261 video.

i'd love to get additional participants interested in pursuing both the high
quality video streams as well as peristent venues based on specific interests.


the following persistent spaces are usually always on:

high quality DV mulitcast stream (requires client from

my personal space (using vic and rat): video; audio
Gurcharan S. Khanna
Associate Director
Research Computing
Dartmouth College
gkhanna at dartmouth.edu 
office: 603-646-1644

--- Tom Coffin wrote:

hi Wenjun

You certainly raise an intersting topic. One which I too
am very interested in. From my perspective, the persistant
nature of this tool has two main parts. the first is it needs
to be "on". The second it needs to be used.

The first "being on" is dependant on operators maintaining the
equipment so that it is persistantly functioning - At ACCESS
we have many nodes and have all systems running but with the
audio muted. At any time you can come to our venue (ACCESS DC)
and see what's happening. This sounds easy, but it does take some
effort and engangement to be constantly monitoring the systems.

The second "using it" is a bit trickier because it also depends
upon the consciousness of the people working in and around
these nodes. Persistant presence between sites is a new
paradigm and it will take some time for it to become a comfortable
modality. But, with time (given that the equipment is continuously
maintained) people will start to interact spontaneously.
As an operator monitoring and trying to maintain a persistant
environment I have had many spontaneous and informal
communications but for the most part those still revolve around
scheduled events or the preperation of scheduled events.

The deployment of personal interface machines will help
awarness of the persistant capability of this tool. Along with
deployment I have encouraged the people who receive these
machines to keep them "on" all the time - Which they do, but
they still rarely use them. I think this is because many
of their colleagues still do not have these systems on their
desktop. That should change as these systems become more common.

At 09:29 AM 3/12/2003 -0600, Wenjun Liu wrote:
   >My name is Wenjun. I am the node operator for The University of Chicago
   >Hospital node and a guest graduate student of Futures Lab at Argonne.
   >During my one and half years of node operating, I got many questions
   >concerning AG use and still don't have satisfactory answers to some of
   >those questions by myself. Reading the new AG-USERS mailing list, I
   >realized that there are many experienced AG users and developers out there
   >in the large community of AG. I believe that some of you may help me with
   >those questions.
   >I understand that AG is supposed to be a persistent space that supports
   >both formal and informal communications. I can see how persistence works
   >in MUD or mailing list but hardly see persistence works in AG. Yes, there
   >is this virtual venue metaphor and Access Grid Lobby is open 24/7 with
   >many nodes always parked there, some with video of empty rooms, some with
   >blue screens. I hardly saw anyone uses this persistent space in a
   >non-trivial way, that is, really gets something communicated besides empty
   >room videos and "Do you hear me?" testing calls. Almost all communications
   >I observed in AG are done in a very formal way: they are pre-scheduled
   >with AG Schedule (I counted 2019 such scheduled events from September 1999
   >to February 2003). Hence, AG users (not node operators) usually come to a
   >node at a scheduled time; have their meetings; immediately log off (by
   >node operators) right after the meetings; and leave. And, by the way, it
   >seems that real AG users (not node operators) hardly appreciate the
   >virtual venue metaphor. They simply need to know how to get to that
   >physical conference room. Only node operators care about virtual venue:
   >it's their job to know it (by "job" I mean I would not want to know it if
   >I could). 
   >Because persistent space and informal communication seem to be very
   >important concepts in CVE technology, I wonder why they are not being used
   >in AG. I tried to read and parse huge amount of AG virtual venue log files
   >in hope of finding any such informal communication done in AG persistent
   >space. No luck so far. Of course, there are physical room constraints on
   >unscheduled AG use. With many PIGs up and running, do people have better
   >chance to casual encounter with each other? Did any of you use AG
   >informally? How? Considering that we can easily reap the benefits of
   >persistence in MUD and mailing list, I wonder why we can't do so in AG. Is
   >this a user problem (for AG-USERS) or a technical problem (for AG-TECH)?
   >Thanks for sharing your experience and insight.

Tom Coffin .......................... tcoffin at ncsa.uiuc.edu 
--- end of quote ---

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