Active multicast service architecture for user customized multimedia data transmission over ATM networks

This paper proposes a new ATM multicast scheme within the framework of an Active Multicast Service Architecture (AMSA) that supports user customization of multicast service. The customization is achieved by injecting and invoking user specific programs to shared network resources such as routers and switches. The multicast scheme also allows dynamic joining and (or) leaving of members of different capabilities and quality of service requirements. A prototype of the multicast scheme was developed to verify the major functions of the AMSA and to demonstrate the feasibility of customizing network services within the active service architectural framework . The prototype supports QOS negotiation, non-uniform links QOS, resource reservation and filter program injection. The development platform used consists of virtual ATM switches (implemented as light-weight threads in four workstations for simulating real ATM switches) interconnected via a real FORE ATM switch. The data links between these virtual switches are AAL-5 virtual circuits that enable actual QOS reservation. The signaling of the virtual switches is implemented via CORBA links connecting the CORBA daemons residing in the virtual switches. Experimental results show that the prototype of ATM multicast scheme is efficient and flexible in satisfying the requirements of heterogeneous users.