Research On Architecture And Optimization Methods For New Generation Spectrum Efficient Optical Network

The Internet traffic keeps on increasing drastically,which makes spectral efficiency of an optical network more and more important.The recently emerging flexible grid elastic optical network(EON)can greatly improve the network spectral resource utilization compared to the convertational dense wavelength division multiplexing(DWDM)network.First,with the backbone network gradually migrating from a fixed grid network to a flexible grid network,we employ the multi-path sub-band virtual concatenation(VCAT)technique to ensure the coexistence of the fixed grid and flexible grid techniques,which is referred to as mixed grid optical network.To optimally design this type of network,we develop a mixed integer.linear programming(MILP)model and an efficient heuristic algorithm based on spectrum window planes(SWPs)for lightpath routing and spectrum allocation(RSA).Simulation results show that the proposed multi-path VCAT scheme can significantly improve the overall spectrum resource utilization of the mixed grid optical network,thereby ensuring the efficient use of the network spectrum resource in the course of the migration from a pure fixed grid network to a pure flexible grid network.In addition,to upgrade a metro optical network,we introduce a special EON paradigm called ultra dense-wavelength switched network(UD-WSN),which implements the bandwidth provisioning mode of "Single-User-Single-Wavelength".For performance evaluation,an efficient S WP-based heuristic algorithm is proposed.We evaluate the network performance from the perspective of techno-economy and bandwidth blocking probability(BBP),and the simulation results show that UD-WSN can achieve a network bandwidth utilization close to the pure optical transport network(OTN)and OTN over DWDM network,however,at a much lower cost and a much lower power consumption,and with a much shorter end-to-end service connection latency.