Performance Study of Asymmetric Traffic Load for OBS Ring Networks

A novel MAC protocol is named beforehand bandwidth reservation (BBR) based on reserve the empty slots in the next big-slot cycle is proposed for OBS ring networks by control channel. To evaluate optimal utilization of channel bandwidth under unbalance traffic scenario, this paper studies packet scheduling based on statistic TDM scheme to allocate the idle slots. For achieving best performance, the length of the big-slot cycle is studied with a view to investigating performance divergence. In additions, a multi-token protocol is compared with the BBR protocol. According to simulation results, the BBR ring using the statistic TDM approach achieves the best bandwidth utilization, while the multi-token protocol achieves the worst performance.