Clustering Based Scheduling: A New Approach to the Design of Scheduling Algorithms for WDM Star Networks

Scheduling algorithms in wavelength division multiplexing (WDM) single hope networks aim at producing an effective schedule in order to improve the networks´ performance. Up to now, popular approaches schedule network traffic based on nodes´ requests which are considered in a sequential service order. This paper presents a novel packet scheduling scheme for WDM star networks based on clustering techniques. Our clustering based scheduling algorithm (CBSA) organizes the nodes of a network into groups (i.e. clusters) according to the number of their requests per channel and then it defines their transmission priority beginning from the nodes belonging to the cluster with greater demands and ending to the nodes of cluster with fewer requests. The simulation results have shown that the proposed approach improves network performance since it results in higher network throughput keeping mean packet delay at low levels in comparison with conventional scheduling algorithms.