Date Added: Apr 2011
To reduce the cost of fault management in the all optical networks, it is investigated to detect the degradation of optical signal quality solely at the terminal points of all-optical monitoring paths. The monitoring paths must be routed so that all single-link failures can be localized using routes information of monitoring paths where signal quality degradation is detected. However, routes computation for the monitoring paths that satisfy the above condition is time consuming. This paper proposes a procedure for deriving the lower bounds of the required number of monitoring paths to localize all the single-link failures, and an efficient monitoring path computation method based on the derived lower bounds.