Routing Bandwidth-Guaranteed Paths with Restoration in Label-Switched Networks Routing Bandwidth-Guaranteed paths with Restoration in Label-Switched

In this paper, we investigate distributed algorithms for routing of end-to-end LSPs with backup restoration in the context of label-switched networks. Specifically, we propose a new concept of the Backup Load Distribution (BLD) matrix that captures partial network state and eliminates the problems of bandwidth wastage, pessimistic link selection, and bandwidth release ambiguity. We describe two new, distributed routing algorithms that utilize the BLD matrix and require a bounded amount of run time. We can realize these algorithms in the current Internet architecture using the OSPF extensions for Quality-of-Service (QoS) routing [1,2] to exchange the proposed BLD matrix among peer routers/switches.