Multimedia group communication emerges to focal interest at mobile devices, enriching voice or video conferencing and complex collaborative environments. The Internet uniquely provides the benet of scalable, dynamic group communication services, vitally aiding commonlylimitedmobileterminals. ThetraditionalInternet approach of Any Source Multicast (ASM) routing, though, remains hesitant to spread beyond limited, controlled environments. It is widely believed that simpler and more selective mechanisms for group distribution in Source Specic Multicast (SSM) will globally disseminate to many users of multicast infrastructure and services. Mobility management for the recent SSM standard is under debate SSM group session initiation up until now remains unsupported by the Session Initiation Protocol (SIP). In this paper we present straightforward extensions toSIPfornegotiatingSSMsessions. SIPprotocolspecicationsandsemanticarecompatiblyextendedwithout addingnewSIPmethods. Wewillintroduce...
Thomas C. Schmidt, Matthias Wählisch, Hans L.