Efficient Multicasting for
               Interactive Multimedia Applications



             Clemens Szyperski and Giorgio  Ventre



                        The Tenet Group
            International Computer Science Institute
                              and
                   Computer Science Division
                       Department of EECS
               University of California, Berkeley

          e-mail: {szyperski,ventre}@icsi.berkeley.edu



                 ICSI Technical Report TR-93-017

                           March 1993



                            Abstract
A specific class of multimedia applications is expected to be  of
importance  for  future  communication  networks: Multi-Party In-
teractive Multimedia (MIM). Based on the isolation and character-
ization  of  MIM  applications, concrete network support require-
ments are derived in this paper. The varying  degree  of  connec-
tivity,  the  vastly different sizes in terms of participants and
the reliance on a guaranteed Quality of Service make MIM  support
a  difficult problem.  Starting with the definition of multimedia
communication abstractions, principles of solutions are sketched.
For  an  important subclass of applications  a particularly effi-
cient and practicable alternative implementation based  on  half-
duplex  channels  is  introduced. Finally, interfaces at both the
transport  and network layers are considered.