Packet Switching and Replication of Multicast Traffic by Crosspoint Buffered Packet Switches

Multicast traffic is expected to increase in packet-oriented networks by the inclusion of broadcast and multimedia-on-demand services. In addition to the high performance for unicast services, combined input-crosspoint buffered (CICB) packet switches have intrinsic properties that are favorable for switching and replication of multicast packets. In this paper we study the performance of CICB packet switches, including those with dedicated and shared crosspoint buffers (SMCB), both under multicast traffic. Furthermore, we propose arbitration schemes for shared-buffer packet switches to handle multicast traffic and study their performance on switching-replication efficiency. We show that the SMCB switch efficiently handles multicast traffic with uniform distribution of fan outs, and that its achievable throughput is comparable to that of a CICB switch. This property, combined with the efficient memory utilization, makes the SMCB switch an attractive solution for unicast and multicast networks.