Patent ID: 7450496

Claim:
A mesh telecommunication network having a plurality of nodes comprising: a destination node; a source node for selecting a restoration path in said mesh telecommunication network by sending a first message along a service path to the destination node, receiving, in response to the first message, a second message from the destination node via a return path, the second message containing an array storing a restoration link capacity for each link in the return path not in the service path, wherein at least some of the nodes in the return path update the array upon receipt of the second message and wherein, if said restoration link capacity is shared, said restoration link capacity is computed as follows restoration ⁢ ⁢ link ⁢ ⁢ capacity ⁢ ⁢ w k = { ɛ if ⁢ ⁢ C k ≥ size w 0 ⁢ k * ( size - C k ) / size if ⁢ ⁢ C k ≺ size ⁢ ⁢ and ⁢ ⁢ M k + size ≤ R k , ∞ M k + size ≻ R k where M k is the number of channels needed on fiber link k over all possible failures of a previously selected service path for a connection request V, w 0k is an initial weight of link k, R k is a total number of channels reserved for restoration on each optical link k, C k represents spare restoration channels on optical link k, size is a connection size, and parameter ε is a value defined to be less than the weight on a link, and if said restoration link capacity is dedicated, said restoration link capacity is set to available free channels on said link; selecting a restoration path through the network from the source node to the destination node using the array; and reserving resources for the restoration path in the network.