A simple adaptive wormhole routing algorithm for MIMD systems

This paper describes a new adaptive wormhole routing algorithm for distributed memory MIMD systems. The algorithm uses the absolute sum of the difference in the coordinates of the nodes, as a measure to determine which of the available output channels the packet must be routed through. Thus, the routing decision is local, involves simple computations and provides maximum adaptivity to the traffic. The adaptivity of the packets that have resided in the network for a long time, is restricted to the shortest path to their destination, which ensures livelock freedom. In order to avoid deadlock, packets are buffered and then reintroduced when routing paths become available. The algorithm maps to a simple architecture.