A Resilient Path Management for BGP/MPLS VPN

BGP/MPLS VPN is recently receiving much attention from industries and standard bodies. It enables ISP to provide IP-service with QoS guarantee to the customers over shared MPLS backbone. In this paper, we present a resilient path management mechanism for BGP/MPLS VPN. An existence condition for finding fast backup path which satisfies the resilience constraint is derived for a full mesh BGP/MPLS VPN. It is based on Hamiltonian cycle which is a minimal set of traversing links for a given graph. A simple path finding algorithm with O (n) computational complexity is presented. Finally, we develop a decomposition theorem which enables the approach to be extended to the hierarchical MPLS backbone which is well scalable in a full mesh structure, using MPLS label stacking technique.