Virtual Topology Design for OBS Optical Networks

Burst loss and delay are two main issues in optical burst switching (OBS) networks. In OBS, if the hop-count between the source-destination node pair can be reduced, both the control packet and the corresponding data burst will suffer less risk of contention, and the delay caused by offset time will be reduced as well. Therefore, it is meaningful to overlay OBS upon a virtual topology with reduced network diameter and average hop-count. In this paper, a novel algorithm LWMD (Least Weight Minimum Diameter) is proposed to construct virtual topology for this goal. Based on the virtual topology obtained, two traffic accommodation schemes are also designed to provision wavelengths for a given traffic matrix. This provides a comprehensive solution to improve the performance of OBS networks.