Multi-Granular Optical Switching: A Classified Overview for the Past and Future

摘要: The wavelength routed network (WRN) accommodates traffic demands by establishing lightpaths along the corresponding routing paths. of each lightpath is switched individually traditional optical cross-connects (T-OXCs) to transit traffic. Due explosion and resulted growth in number, WRNs face a challenge increase node-size (i.e., port number T-OXC) as well associated cost control complexity. As an alternative solution, waveband switching (WBS) introduced group multiple wavelengths together band or fiber. Whenever possible, requires just single at multi-granular cross-connect (MG-OXC). One fundamental problem WBS networks assignment (RWA). With major goal minimizing numbers networks, optimal RWA was shown be NP-Hard. In literature, various Integer Linear Programming models are proposed optimally solve small-size problem, many heuristic algorithms provide practical solution for large-scale networks. this work, we comprehensively review literature studies on topics covered include architecture, solving strategies, future challenges conversion, protection, rerouting We aim presenting classified view based aspects including pattern, node grouping policy, configurations. investigate factors that affect reduction blocking minimization addition, explore several unique features conversion rerouting, which point out open deserve further studies.