Survivable routing and regenerator placement in optical networks

The large capacity of WDM optical networks facilitates the transportation of impressive volumes of traffic, which make survivability schemes that can reroute traffic upon a failure in the network highly important. Besides survivability, the signal quality in optical networks, which degrades along its path due to physical impairments, needs consideration. In this paper, we consider the design problem of where to place regenerators in the network such that both the primary and backup lightpaths for a (predicted) traffic matrix obey the impairment constraints. We study the survivable routing and regenerator placement problem under dedicated and shared protection schemes, analyze the complexity of both problem variants, and subsequently propose efficient algorithms to solve or approximate them.