Multicast Support in Input Queued Switches with Low Matching Overhead

This letter addresses the scalability problems induced by high complexity of multicast scheduling algorithms in high-speed switches. Based on a two-phase (request-grant) scheduling scheme in a Nx N switch, a more scalable approach instead of traditional iterative schedulings is presented, which reduces the matching overhead from O(kN) to O(N) by selecting one head-of-line cell for requesting when k multicast queues are allocated at each input port. Simulation results show that the proposed algorithm exhibits a good switching performance in terms of throughput and average delay under various traffic patterns.