Fairness control in wavelength-routed WDM ring networks

We investigate a threshold-based wavelength allocation scheme in order to support fairness and service differentiation in WDM unidirectional ring networks. A ring network can handle different classes of traffic streams, which differ by their hop-counts (i.e., the number of hops used from source to destination). We assume that for each class of traffic, call interarrival and holding times are exponentially distributed. In such a network, classes of calls with smaller hop-counts, experience lower blocking rates than ones with greater hop-counts. In this paper, a multi-threshold wavelength allocation scheme is proposed to provide equal blocking probabilities experienced by different classes. A recursive simulation-based algorithm is designed to numerically compute the optimal thresholds. Simulation results compare the performance of our proposed scheme, with that of complete sharing and complete partitioning schemes