A heuristic for combined protection of IP services and wavelength services in optical WDM networks

In IP-over-WDM networks, wavelength services (circuits) are often protected by dedicated backup circuits. The upcoming deployment of 100G transmission systems will induce huge under-utilization of backup resources. Network utilization can be boosted by loaning the idle backup circuits to preemptible IP/packet services. Unfortunately, in the event that a backup circuit used for IP services fails, all traffic on that circuit is preempted. It is therefore critical to carefully select the backup circuits for IP/packet services such that, in a failure scenario, the IP topology is not disconnected. In this paper, we propose a heuristic algorithm for jointly provisioning wavelength and IP services along with re-use of backup wavelength capacity. We observe that our integrated heuristic algorithm enables much higher resource utilization compared to our earlier two-step provisioning approach, allowing up to 10% additional decrease in wavelength channels usage, and that we can still ensure combined survivability of both IP and wavelength services.