Packet scheduling algorithms for optical packet switch with shared WDM buffers

In this paper, a buffer control strategy called limited greedy mode (LGM) is presented to handle fibre delay line (FDL) contentions which often occur in optical packet switch with shared FDL-buffer. In order to make full use of the FDL-buffer, three scheduling algorithms based on the LGM, i.e. Shortest Queue Based on Limited Greedy Mode (SQLGM), Increasing Queue Based on Limited Greedy Mode (IQLGM) and Shortest Queue Considering Output Void (SQCOV) are proposed. Performances of these three algorithms are evaluated by simulation experiments. Simulation results show that the SQCOV achieves the best performance. In addition, the buffering performance of shared FDL-buffer also depends on the greedy degree of LGM and the granularity of FDL. Copyright (C) 2009 John Wiley & Sons, Ltd.