Bandwidth guaranteed restorable multicast virtual private networks

We propose heuristic algorithms to compute optimized tunnel paths between single source and multiple destinations in a multicast VPN scenario. This is achieved by first building up a CPE based layout for the minimal cost (MC) multicast VPN problem and then selecting few core routers strategically. These we call active paths. We also compute backup paths for every active path for the sake of restorability, allowing sharing of backup bandwidth. This is also a type of online routing problem. For comparison purposes, we also formulate a mathematical model of the MC-multicast VPN problem using integer linear programming and solve it using the CPLEX tool.