Nodes’ clustering in WDM star networks with real-time traffic

This paper proposes a novel scheduling scheme, namely node clustering with prioritized scheduling (NOC-PS), which is designed to handle real-time traffic in wavelength division multiplexing (WDM) star networks. NOC-PS is based on clustering techniques, while it takes into account the priority information of data packets. The clustering process aims at organizing the network nodes into groups in terms of their packetspsila requests per channel. Then, NOC-PS rearranges the nodespsila service order beginning from the cluster with long-length requests and ending to the cluster with short-length requests. The novelty of NOC-PS is that it applies separate clustering to nodes with high and low priority packets, while it also differentiates their scheduling, since high-priority packets have the privilege of being scheduled prior to low-priority ones. The simulation results indicate that the proposed scheme leads to a significantly higher throughput-delay performance for real-time traffic, without sacrificing the performance of non-real-time traffic.