Impact of spare capacity reuse on multi-class lightpath survivability differentiation

This paper studies the impact of the selective reutilization (both before and after failure occurrence) of spare capacity, allocated for high class lightpath protection, to differentiate the survivability performance of two distinct low lightpath classes. In particular while the high lightpath class exploits shared path protection, low lightpath classes resort to best effort dynamic restoration. Numerical results show that the survivability of the low class exploiting spare capacity resources only after failure occurrence is bounded and always higher than the survivability of the low class exploiting spare capacity even before failure occurrence. In addition latter class survivability heavily depends on the amount of spare capacity allocated for high class lightpaths.