A simulation study of packet forwarding methods over ATM: SBR evaluation

The desire to switch ATM cells at high speed and forward data packets in a connectionless (CL) manner poses a challenging architectural difficulty that has not yet been satisfactorily resolved. This difficulty is mainly due to lack of a packet concept in ATM switches-a packet is a level-3 abstraction, totally hidden from the switch. The switch-borne router (SBR) is a proposed switch/router architecture that makes it possible to switch CL packets at very high speed using ATM technology. This paper introduces the SBR and compares its performance with other forwarding methods using a simulator. Compared to other methods, the SBR allows for a significantly smaller number of open/close VC operations per second, has less buffering requirement, and achieves higher throughput. The same results hold using a real-life Internet packet trace as well as using traffic drawn from a synthetic workload generator