The Effects of Multi-Layer Traffic on the Survivability of IP-Over-WDM Networks

The survivability of backbone networks to failures is an on-going concern. This paper investigates survivability strategies for IP-over-WDM networks in a multi-layer framework where traffic originates at each layer. We present an optimization- based formulation of performing recovery mechanisms at the bottom layer for both layers of traffic in two cases: With capacity sharing between backup paths of the traffic in two layers and without. We then study and compare spare capacity requirements under multi-layer traffic ratios and the impact of network connectivity. Numerical results indicate that, in such a wavelength-based optical network, implementing survivability of all traffic at the bottom layer can be a viable solution with significant advantages.