The IP over ATM Mailing List Archive by date

[brutzman@cs.nps.navy.mil (Don Brutzman)]

Your metaquestion "does it matter" that ATM multicast is unlikely to
match IP-multicast is pretty interesting.  The examples you present
are one-to-many or several-to-many.  A small number of one-way trees
can likely suffice in such scenarios.

However there is another existing application that is many-to-many:
large-scale virtual environments (VEs) as currently implemented using
the Distributed Interactive Simulation (DIS) protocol.  Other
implementations of large-scale networked entity interactions are
likely to emerge in connection with the Virtual Reality Modeling
Language (VRML) version 2 development effort.  With 100,000
simultaneous players as a nominal goal, ATM-level bandwidths and
latencies will eventually be needed.

The following paper addresses most of the problems inherent in scaling up.
It does not discuss ATM directly but the concepts apply to your metaquestion.


    Internetwork Infrastructure Requirements for Virtual Environments
                                    
      Donald P. Brutzman, Michael R. Macedonia and Michael J. Zyda
         Computer Science Department, Naval Postgraduate School
                   Monterey California 93943-5000 USA
                  408.656.2149 voice, 408.656.3679 fax
               {brutzman, macedonia, zyda}@cs.nps.navy.mil


     Abstract.  Virtual environments (VEs) are a broad multidisciplinary
research area that includes all aspects of computer science, virtual
reality, virtual worlds, teleoperation and telepresence.  A variety of
network elements are required to scale up virtual environments to
arbitrarily large sizes, simultaneously connecting thousands of interacting
players and all kinds of information objects.  Four key communications
components for virtual environments are found within the Internet Protocol
(IP) suite:  light-weight messages, network pointers, heavy-weight objects
and real-time streams.  Software and hardware shortfalls and successes for
internetworked virtual environments provide specific research conclusions
and recommendations.  Since large-scale networked are intended to include
all possible types of content and interaction, they are expected to enable
new classes of interdisciplinary research and sophisticated applications
that are particularly suitable for implementation using the Virtual Reality
Modeling Language (VRML).

To be presented at the Virtual Reality Modeling Language (VRML) Symposium,
San Diego Supercomputing Center, San Diego California, 13-15 December 1995.  
Available at http//www.stl.nps.navy.mil/~brutzman/vrml_95.ps



all the best, Don
-- 
Don Brutzman   Naval Postgraduate School, Code UW/Br         work 408.656.2149
               Monterey California 93943-5000 USA [Root 200] fax  408.656.3679
AUV Underwater Virtual World ftp://taurus.cs.nps.navy.mil/pub/auv/auv_uvw.html