A backup-reservation-based dynamic wavelength assignment scheme for WSONs

Proposed in this paper is a backup-reservation-based wavelength assignment (BRWA) scheme for wavelength switched optical networks (WSONs). The rationale behind the idea is to reserve a backup lambda in addition to the primary one for a lightpath if the number of the available lambdas can meet certain constraints. Therefore a threshold is defined to determine whether to reserve a backup lambda according to the number of the available lambdas. Simulation results show that, by setting a proper value for the threshold, BRWA can reduce the blockings caused by contention efficiently thus performs much better in total blocking probability than the two traditional schemes.