Irregular torus networks: deadlock avoidance and throughput analysis

The irregular torus, a class of topologies proposed for metropolitan area networks, is torus-like, and thus more reliable than the bus and ring topologies. There is a routing algorithm for the topologies which is space and time efficient so that it is suitable for high-speed implementations. In addition, it is robust to topology perturbations due to network growth and node/link failure. A buffer management is proposed to prevent store-and-forward deadlock for routing in the irregular torus, and the throughput of a typical irregular torus network is analyzed. Store-and-forward deadlock is avoided by a buffer management whose storage requirement and control complexity at a node are both constant with the size of a network. The throughput of a typical irregular torus network is shown to be within a constant factor of that of a square torus. Hence for a large number of nodes, it is much higher than the throughput of a bus, ring or tree