Discovery of BGP MPLS VPNs

BGP/MPLS VPN is a mechanism defined in IETF RFC 2547 that allows service providers to use their IP backbone to provide VPN services. This mechanism is based on using BGP to distribute VPN routing information to the routers in the backbone network and using MPLS to forward VPN traffic. MPLS tunnels are created dynamically when needed, which relieves service providers of pre-provisioning tens of thousands of tunnels. BGP/MPLS VPNs allow service providers to define any arbitrary topology with any number of nodes in a VPN. The service provider can create multiple VPNs using the same core network. Currently most of the service providers track 2547 VPNs either manually or by using a provisioning database. Algorithms described in this paper aims at automating this VPN discovery procedure. Using our algorithms service providers can automatically discover VPNs that have already been configured using the current network configuration information.