Fault-Tolerant Wormhole Routing in Two-Dimensional Mesh Networks with Convex Faults

Faulty blocks are expanded, by disabling nodes, to form rectangular faults in many existing works to facilitate the designing of deadlock-free routing schemes for meshes recently. In this paper, faulty blocks are di€used to be rectangular faults, which are composed of faulty and fault-di€used nodes. These rectangular faults are then shrunk, by recovering fault-di€used nodes, to form convex faults for reducing the number of nodes disabled. Simulation results show that up to 70% of the disabled nodes, which are needed to form rectangular faults, can be recovered if the number of faulty nodes is less than 10% of the total network nodes. Both non-adaptive and adaptive fault-tolerant routing algorithms are proposed to handle these resulted convex faults. The adaptive routing algorithm is enhanced from the non-adaptive counterpart by utilizing the virtual channels that are not used in the non-adaptive algorithm; hence, the number of virtual channels per physical channel used in the adaptive algorithm is the same to that used in the non-adaptive algorithm. Ó 1999 Published by Elsevier Science Inc. All rights reserved.