Criteria for performance improvement in metropolitan area WDM ring networks

In this paper, we present three efficient and combined algorithms suitable for WDM ring metropolitan area networks. The first algorithm determines the input traffic allocation into a multiple buffer architecture at each node. The second algorithm defines an effective access scheme to avoid both the data wavelengths and the receiver collisions. Finally, the third algorithm introduces an effective buffer selection for transmission technique that combines the priority criteria of receiver collisions avoidance and packet age. In this way, we apply a slotted WDMA protocol in order to improve the limited bandwidth utilization that many WDMA protocols for MANs introduce, especially at high loads. The proposed protocol behaviour is investigated through exhaustive simulations assuming Poisson traffic sources. It is proven that we achieve dropping probability and delay reduction, while we manage throughput improvement. Our study concludes with the determination of the required number of buffers per node to maximize throughput.