A Shared-Memory Design for Crosspoint Buffered Switches under Mixed Uni- and Multicast Traffic

In this study, to deal with mixed uni- and multicast traffic, we propose an efficient buffered crossbar switching architecture called MQ-SCPX switch. Based on a guess to the load share percentage of the mixed uni- and multicast traffic, the need of buffering resource for unicast traffic might be lower, while the multicast traffic becomes more. The MQ-SCPX switch is separated into one unicast section and one multicast section, respectively. To ease off the effectiveness of the multicast HOL blocking problem, we adopt multiple buffers for each input port in the multicast section. Also, to reduce the memory size of the buffered crossbar, we use a shared memory mechanism for the buffered crossbar. Simulations under different proportions of unicast to multicast traffic have been done to evaluate system performance. The simulation results show that the MQ-SCPX switch can achieve dramatic service quality for multicast applications and has great capability to supports both unicast and multicast services.