A threshold-based blocking differentiation mechanism for networks with wavelength continuity constraint

This paper presents a centralized admission control mechanism to differentiate the blocking probability experienced by various service classes in lightpath switched WDM networks with wavelength continuity constraint. The control mechanism, referred to as threshold-based blocking differentiation (TBDiff), is based on multiple class-thresholds, which specify the minimal amount of wavelengths that must be available along the route, prior to accommodating a request for a given service class. Blocking probability of the TBDiff mechanism is characterized by means of both an event-driven simulator and an approximated analytical framework that takes into consideration the link load correlation. Obtained results demonstrate that the TBDiff mechanism yields significant blocking differentiation among the service classes, without excessively increasing the overall (average) network blocking probability.