SRLG failure localization with monitoring trails in all-optical mesh networks

This paper considers the problem of out-of-band failure localization in all-optical mesh networks using bidirectional monitoring trails (bm-trails) for localizing any shared risk link group (SRLG) failure. We firstly prove NP-completeness for the problem of unambiguous failure localization (UFL) under the considered SRLG failure scenario with the minimum number of bm-trails. Next, a necessary and sufficient condition is provided for the feasibility of the formulated problem, which further serves as the foundation of the proposed heuristic, namely Link Code Construction (LCC). Extensive simulation is conducted on hundreds of randomly generated planar topologies to verify the proposed approach and compare it with some previously reported counterparts in terms of the number of required bm-trails and the computational efficiency.