On multicast support for shared-memory-based ATM switch architecture

Because of its superior performance characteristics in terms of cell loss and throughput for a given memory space, shared-memory ATM switches have gained significant importance in handling bursty traffic in ATM networks. Because of its increased effective load, multicast traffic requires an even greater increase in switching capacity than a shared-memory-based ATM switching system can provide. In order to support multicast operations with a memory-based switching system, the replication and storage methods used for multicast ATM cells for switching purposes become important. Various ways used to support multicast operation with a shared-memory-based ATM switching system have been categorized into several classes. Performance evaluation shows that the class of single-write single-read multicast scheme with output mask (CSWSR-w-OM) implementation overcomes the memory bottleneck involved with replication of multicast cells. It also provides superior performance for a given memory space employed in the shared-memory switching system in comparison to other classes of multicast schemes.