Priority-based minimum interference path multicast: routing algorithm in optical virtual private network

While the “Virtual Private Network (VPN) over Internet” is cost-effective and flexible, it suffers from the difficulty of providing adequate transmission capacity for high bandwidth services. Hence a Dense Wavelength Division Multiplexing (DWDM) based “Optical VPN (OVPN)” technology has been regarded as a good alternative for realizing the future VPN services. To improve the transparency and data rate of OVPN, it is critical to consider the problem of Routing and Wavelength Assignment (RWA) for transmission capacity utilization. This paper proposes a Priority-based Minimum Interference Path Multicast Routing (PMIPMR) algorithm, a new routing algorithm which finds alternative routes based on node priorities and Virtual Source (VS) nodes that has both splitting and wavelength conversion, and then chooses a path that does not interfere with potential future multicast session requests when congestions occur in the network. The PMIPMR algorithm reduces blocking rate significantly and increases the wavelength utilization by avoiding congestion in future multicast session requests. We measured the performance of the proposed algorithm in terms of blocking rate and the resource utilization. The simulation results demonstrate that the PMIPMR algorithm is superior to the previous multicast routing algorithms using the Capability-based-Connection algorithm based on Capability-based-Priority and Spawn-from-VS methods.