Optical networks and Internet Protocol/Multi-Protocol Label Switching (IP/MPLS) based networks have been traditionally designed and operated by separate departments of network operators. Likewise, both layers have always represented different business areas for system providers, which maintain different product lines for each of them. However, network operators have an IP/ MPLS over WDM architecture. The main drivers for this unique transport network are the cost savings achieved by simplifying thenetwork infrastructure.
Thanks to the advent of reconfigurable optical equipment and a multilayer control plane, 1 + 1 node protection at the IP layer in each location is no longer required. This work compares two resilience strategies on multi-layer network dimensioning: dual-plane protection and a multi-layer shared backup router (MLSBR). Based on the results of this paper, a MLSBR provides a significant reduction (up to 24%) on the required IP equipment in comparison with the IP protection approach.