Submission for Photonic Network Communications, Special Issue on Ip-over-wdm

Due to the fast increase of Internet traffic and the enormous bandwidth potential of alloptical transport networks based on Wavelength Division Multiplexing, an IP-over-WDM network scenario is likely to be widespread in future communication networks. At the same time, IP networks are becoming more and more mission-critical. Hence, it is of paramount importance for IP-over-WDM networks to be able to recover quickly from frequently occurring network failures. This paper explains how Multi-Protocol Label Switching (both electrical and optical) recovery mechanisms can be important to reach that goal. Moreover, a novel MPLS recovery mechanism called Fast Topology-Driven Constrained-Based Rerouting is presented. Different MPLS recovery mechanisms are compared to each other. Special attention hereby goes to the additional capacity that is required to recover from frequently occurring failures.