Unambiguous switching link group failure localization in all‐optical networks

Abstract

In this article, we investigate the Advanced Global Neighborhood Failure Localization (AG‐NFL) monitoring trail (m‐trail) approach, which provides ultra‐fast all‐optical restoration for any shared protection scheme. In contrast with its previous counterparts, AG‐NFL separates the management tasks of protection switching and link maintenance, and focuses on the identification of the proper switching actions in a timely manner rather than unambiguously localizing link failures. We form switching link groups at each node, that is, links whose failures do not have to be distinguished from each other, for example, because their corresponding switching actions can be performed at the same time. Forbidden link‐pairs are introduced to identify the minimal set of conflicting switching actions, which minimizes the number of switching link groups. Furthermore, in order to minimize the number of m‐trail reconfigurations upon dynamic traffic, we analyze the AG‐NFL performance in four different m‐trail design scenarios with decreasing dependency on the data plane. We prove that AG‐NFL is NP‐complete, and we propose an efficient heuristic to solve it. We demonstrate through simulations that unambiguous localization of switching link groups instead of single link failures leads to a significantly improved m‐trail performance both in wavelength resources and the number of required transponders, while signaling‐free restoration is still provided. © 2017 Wiley Periodicals, Inc. NETWORKS, Vol. 70(4), 327–341 2017