Adaptive Virtual-Channel Flow Control in MIN Switches with Bursty Traffic

This paper is concerned with performance analysis of the MIN (Multistage Interconnection Network) with virtual channel flow control under bursty traffic. In the past, many research efforts have been devoted to the performance analysis of buffered MIN switches. Most of these analyses, however, assume that a burst of cells is indivisible when transferred across stages of a MIN switch, or that the traffic consists of discrete packets of uniform length. The effect of employing virtual-channel flow control to process burst of varying lengths through the MIN switch remains largely unknown at present. In this paper, we consider the use of virtual channels to make efficient use of MIN physical link resource. We derive closed forms for switch latency in term of some system parameters. We also construct a simulator for the proposed MIN. Simulations are based on various different kinds of network parameters. Simulation results are compared against the analytical results for verifying their accuracy. Extensive simulation has been performed focusing on the relationship among packet delay and burst length, virtual channel number and virtual channel length. We proposed an auto-adjusting virtual channel allocation method, namely Adaptive Virtual Channel Allocation Policy or AVP. This proposed approach can always provide a better performance than those with fixed virtual channel size. This is true with different or varying degrees of traffic bursts. We use simulation to prove this.