Patent ID: 7886079

Claim:
A method, comprising: receiving one or more path computation requests from path computation clients (PCCs) in a first network domain at a first border router (BR) arranged at the border of the first network domain and a second network domain; learning of a path computation element (PCE) in the second network domain at the first BR arranged at the border of the first network domain and the second network domain; informing the PCE in the second network domain of path computation information for the first network domain; detecting a backup event in the first network domain; and in response to the backup event: establishing one or more tunnels between the first BR arranged at the border of the first network domain and the second network domain and the PCE in the second network domain; passing the one or more path computation requests from PCCs in the first network domain from the first BR, through the one or more tunnels, to the PCE in the second network domain, to be serviced by the PCE in the second network domain using the path computation information for the first network domain; and preventing traffic unrelated to path computation requests from utilizing the one or more tunnels between the first BR and the PCE in the second network domain.