An efficient deadlock-free tree-based routing algorithm for irregular wormhole-routed networks based on the turn model

We proposed an efficient deadlock-free tree-based routing algorithm, the DOWN/UP routing, for irregular wormhole-routed networks based on the turn model. In a tree-based routing algorithm, hot spots around the root of a spanning tree and the uneven traffic distribution are the two main facts degrade the performance of the routing algorithm. To solve the hot spot and the uneven traffic distribution problems, in the DOWN/UP routing, it tries to push the traffic downward to the leaves of a spanning tree as much as possible and remove prohibited turn pairs with opposite directions in each node, respectively. To evaluate the performance of DOWN/UP routing, the simulation is conducted. We have implemented the DOWN/UP routing along with the L-turn routing on the IRFlexSim0.5 simulator. Irregular networks that contain 128 switches with 4-port and 8-port configurations are simulated. The simulation results show that the proposed routing algorithm outperforms the L-turn routing for all test samples in terms of the degree of hot spots, the traffic load distribution, and throughput.