a method and apparatus for selecting failure protection paths in a wdm network . the method exploits wavelength reservation sharing potentials presented by non - concurrent failure events on a plurality of links sharing a link in a protection path . light - weight aggregated link metrics termed “ buckets ” are used to track wavelength reservations for protection paths on individual links in the network . these buckets are then used to construct protection paths with minimized wavelength consumption . the method is employed on individual networking devices in a distributed manner or is used by a centralized network management system to allocate protection paths .