Evaluation of a Path-Finding Algorithm for Interconnected Local Area Networks

The issue of routing in interconnected local area networks (LAN's) is considered. Of particular interest is Source routing where the source station specifies, in an inter-LAN frame, the complete path traversed by that frame. In source routing, a mechanism is needed for the source station to determine a path to any given destination. A pathfinding algorithm has been proposed by Sy, Pitt, and Donnan. In this paper, we evaluate the performance of that algorithm using a simulation model of interconnected token rings. Our evaluation is based on a connection-oriented environment and the assumption that the pathfinding algorithm is used each time a new connection is established. Our results indicate that the algorithm selects paths with good delay and throughput performance for the new connection. As to the existing connections, the algorithm yields good throughput behavior, but may not perform well as far as delay is concerned.