Simulation study of queues' length balance in CICQ switching fabrics

CICQ (Combined Input-Crosspoint Queued) switch fabric is an ideal solution for high-speed routers, which brings its nice distributed parallel scheduling property with no internal speedup required. Studying through resent scheduling algorithms for CICQ, it is shown that the basic reason leading to instability and performance decrease of throughput under nonuniform traffic is the imbalance of input queues. Thus this paper proposes a novel scheduling algorithm based on queues' length balance named MUIQF (Most Urgent Input Queue First). The simulation results show that under any traffic, either uniform or nonuniform, MUIQF can keep the input queues balance, hence achieves 100% throughput and fine stability and time delay performance.