Patent ID: 7961603

Claim:
A method for establishing protection-link-weight of a protection-link protecting a portion of a proposed path between a source node and a destination node, wherein the proposed path has an associated bandwidth requirement and an associated resilience class which indicates a priority level of the proposed path, and wherein the protection-link has an associated protection-factor, the protection-factor being set in relation to the level of protection available on the protection-link, the method comprising the steps of: in a node involved in establishment of the proposed path, determining an available bandwidth value for the protection-link; in the node involved in the establishment of the proposed path, determining a reserved bandwidth value for the protection-link, reserved bandwidth being reserved but not currently used; and in the node involved in the establishment of the proposed path, verifying if the protection-link is present in the proposed path: if so, establishing the protection-link-weight of the protection-link to a value indicating that the protection-link should not be used to protect the proposed path; and if not so and if the resilience class is a high resilience class, verifying if the addition of the available bandwidth value and the reserved bandwidth for the protection-link is equal to or greater than the bandwidth requirement associated to the proposed path: if so, establishing the protection-link-weight of the protection-link by computing the protection-factor associated to the protection-link with the reserved bandwidth on protection-link and the bandwidth requirement associated to the proposed path; and if not so, establishing the protection-link weight of the protection-link to a value indicating that the protection-link should not be used to protect the proposed path.