Origin of route explosion in virtual private networks
Zied Ben-Houidi, Renata Teixeira, Marc Capelle · 2007
Enterprises often have sites that are spread in distant locations. These sites need to interconnect with the same level of privacy as in a local-area network. Virtual Private Networks (VPNs) were introduced to serve this need. A common VPN technology uses Multiprotocol extensions for the Border Gateway Protocol (MP-BGP) and Multiprotocol Label Switching (MPLS). This technology allows a service provider to share its IP backbone among multiple VPN clients while preserving privacy. MPLS tunnels provide traffic isolation, whereas MP-BGP distributes VPN routes. Despite the wide deployment of BGP/MPLS VPNs[1], there have been only few studies to understand their behavior, mostly because of the lack of public data. Prior work focused on BGP convergence [3] and on integrity constraints to ensure connectivity [2].