Multiple path routing algorithm for IP networks

Internet routing protocols, such as Open Shortest Path First (OSPF), compute a shortest path tree from each node to other nodes in the network, using link-state information. Such protocols do not consider the queueing situation at a given node. An alternate path of higher cost may be more convenient to use than the optimum path when a long queue is present at the node. This paper proposes a new Multiple Path Routing Algorithm (MPRA), which uses dynamic shortest path tree mechanisms, load balancing among alternative paths to destination, and path feasibility analysis to avoid network loops. A better-cost model is also introduced. Computer simulations show that MPRA measured parameters (throughput, packet delay, etc.) improve over OSPF by amounts close to 30% for unbalanced networks, and close to 20% for balanced networks. q 2004 Elsevier B.V. All rights reserved.