Waveband Switching

In this chapter, the authors describe and review some of the recent research on WBS, including Multi-Granular optical cross-connect (MG-OXC) architectures that can switch traffic at different granularities. The authors focus on the dynamic online WBS problem, and describe and analyze two reconfigurable MG-OXC architectures in terms of their port count and blocking probabilities. Based on the analyses, the authors then propose a novel dynamic graph-based waveband assignment algorithm in conjunction with adaptive routing. The proposed algorithm employs ant optimization techniques to reduce ports and blocking probability in the network with online traffic in a distributed manner. The authors use simulation experiments to evaluate the effectiveness of the authors’ approach under various parameters such as varying number of ants, varying the number of routes and the wavelength assignment algorithm. The authors’ simulation results show that their graph-based waveband assignment algorithm combined with adaptive routing can achieve a superior performance when compared to other schemes. Furthermore, the authors’ studies shows that even with limited resources, WBS can achieve a low blocking probability and port savings.