Routing in wide area ATM network

Abstract

The performance of an ATM network is greatly influenced by network resource management and control strategies, the protocols and routing algorithms used in the network. Routing is a process in which a node selects one or more outgoing links on which to forward an incoming cells. Since ATM is based on packet switched and circuit switched techniques, the study of routing strategies will look into the various strategies used in the existing packet switched and telephone network. In ATM network a route is defined/set-up during a call connection set-up based on the requested or effective bandwidth allocated. The effective bandwidth was determined at cell level simulation and compared with a mathematical approach. This effective bandwidth was then used in the routing strategies for the assumed ATM network. The simulation work on routing algorithm for ATM network has been carried out using BONES designer simulation software package. First, an algorithm of finding all the possible paths from each source node to each destination node were carried out. These possible routes were used in determining the optimum routes for the various routing strategies such as least distance, least number of nodes and least loaded. The performance of the network with the various routing strategies were evaluated based on the blocking probability of call attempts. Simulation results show that a/fernaffve roMfmg strategy has the lowest blocking probability compared to other simulated strategies.