From: Roy_W_Latham@cup.portal.com
Subject: Re: TECH: Networked VR
Date: Sun, 23 May 93 19:05:38 PDT



Mark Evensen and others expressed interest in networked VR and in
architecture and networked capacity.

Those interested in these topics should look into the research done in
conjunction with the Distributed Interactive Simulation (DIS) effort
sponsored by ARPA, et.al. It is military inspired, but seems perfectly
suited to other types of networked VR. There is a published
application level protocol (now an IEEE standard), there are
communication standards, and there is a network architecture study.
The network architecture is basically distributed, but there are nodes
that filter traffic and servers that perform special functions. There
has been studies of net capacities, and workshops every six months
that take up various issues.

To try to give some feel for the numbers, an FDDI network (20 MB/sec)
will handle only about 2000 entities in a military scenario dominated
by armored vehicles. It took the DIS workshops about two years to
figure out that network users must use extrapolation algorithms to
minimize network traffic, otherwise many fewer will be possible. Voice
traffic is included, but that takes only a third of bandwidth in the
scenario described.

The DIS Workshops are organized by the Center for Continuing
Education, University of Central Florida, Orlando, FL 32816-0177. Tel:
407-249-6100; Fax 407-249-6113. The next workshop should be in late
Sept and cost about $60 to attend.

Roy Latham