Monitoring and alarm management in transparent optical networks

Rapid fault identification and localization in optical networks are crucial due to high data rates. These problems are more challenging than in traditional electronic networks because of optical transparency. In a transparent optical network which does not regenerate optical signals, a fault may propagate to various parts of the network from the origin, and multiple alarms can be generated for a single failure. In order to reduce the number of redundant alarms, simplify fault localization, and reduce the fault localization time, the number and location of fault monitors that are turned on should be optimized for a given network. In this paper, we formulate a problem on the optimal activation of network monitoring devices and propose a solution approach. First, we provide a brief summary of available physical-layer monitoring devices, and then present a scheme for optimal monitor activation. We show the NP-completeness of the problem and present a mixed-integer-linear-program (MILP) formulation of it. We also present a heuristic, whose performance is evaluated through comparisons with the solutions to the MILP, as well as a naive monitor activation approach.