Conducting a Multiparty Multimedia Session over ATM using Hierarchically Encoded Data

Heterogeneous MultiCast (HMC) is a communication paradigm for distributing real-time streams among multiple session participants that have diierent constraints and reception preferences. In HMC, sources ooer streams to the participants , and each participant speciies individualized delity level for each stream he/she wants to receive. Participants can change their speciication in mid-session. The approach is based on sources encoding streams in layers which can be individually ordered. The network provides transport that allows ordering and selective distribution of individual layers. ATM infrastructure is used for connection-based transport and cell switching. However, ATM signaling is enhanced to enable the establishment and management of multipoint, multi-VC connections for carrying multiple layers. The ATM-based network module also supports admission control, and QOS-based multipoint routes.