Research On Minimum Interference Routing Algorithm Based On Extended IGP In MPLS TE Networks

Internet brings the revolutionary change for the world, however the multimedia service such as the rising voice and video call for more demand. It's hard to meet the need just by equipping more infrastructures to extend the capacity of the network. Hence, it's more important to improve the current transmission technology while adding the network resource. MPLS is proposed based on the demand for network development as well as the application experience of many mature technologies. It combines the second layer with the third layer together, which makes full use of the advantage of the switch function and traffic management of the second layer while making the routing function of the third layer get full play.Since IP is lack of predictability and administrable, it is important to control over 80% traffic on the current foundation for the network operators. From the proposed date, Traffic Engineering attracts much attention from the academic industry since it can alleviate the net congestion directly and distribute the network resource reasonably. In addition, it can ensure the QoS indirectly. The paper started around Traffic Engineering technology while it researched on the advantages in MPLS traffic engineering and studied MPLS TE make contribution to improving the net performance and solving QoS guarantee combining existing routing algorithm.A new Minimum Interference Routing Algorithm NMIRA was presented via carefully analyzing Minimum Interference Routing Algorithm (MIRA) and its current improved schemes which were classified as utilizing traffic profile information, adding admission control and reconfirming critical links. This algorithm was composed of off-line phase and on-line phase. The former optimizes the pre-distribution. That is to say, it optimizes the network using the optimization formulas and realizes pre-distributed bandwidth according to the different levels, then builds the selectable links set for online routing phase. The latter realizes dynamic routing, namely, the on-line routing phase adopts an admission control mechanism and utilizes shortest-narrowest routing method to go to a few critical links. It computes link's weight based on the ratio of used and usable bandwidth for all types of traffic in order to lower the algorithm complexity and achieve the purpose of minimum interference at the same time. Simulation results have indicated that the NMIRA performed better than the traditional algorithms such as MHA, CSPF etc in aspects of network request rejection ratio and the total usable bandwidth via adopting reasonable routing and sharing traffic to different links.