Distributed wavelength assignment algorithms and the traffic classification and service (ClaServ) in wavelength-routed all-optical networks

The wavelength-routed all-optical networks are apparently the dominant transport architecture of the future because of the high bandwidth requirement of the expanding Internet traffic. In such networks, the end-to-end lightpath must occupy the same wavelength on each link of the path in the absence of wavelength converters; this is known as the wavelength continuity constraint. This constraint deteriorates the network performance in two aspects: the network traffic blocking probability and the fairness problem. Two wavelength assignment algorithms, the Lightpath Neighborhood Weight (LNW), and the Lightpath End Nodes Neighborhood Weight (LENW) algorithms are developed in this thesis to optimize the network performance. The Traffic classification and service (ClaServ) method are proposed to optimize the fairness problem as well as reduce the average traffic blocking probability. The number of hops the traffic traverses from the source node to the destination node classifies traffic. The combination of the waveband access range method and waveband reservation method provides different services to the classified traffic. This thesis studies two types of networks, the 4 x 4 mesh torus network and the NSFNET, by running the simulation models using the OPNET simulation software. The simulation results show that the LNW and LENW perform better than the First-Fit and Random algorithms in allocating wavelengths in an optical network. The ClaServ method optimizes the fairness problem as well as reduces the network traffic blocking.