An improved algorithm for fault-tolerant wormhole routing in meshes

Boppana and Chalasani [1] present simple methods to enhance wormhole routing algorithms for fault-tolerance in meshes. In this brief paper, we note that one of their algorithms, f-cube4, can further be improved. In particular, we show that only three virtual channels per physical channel are sufficient for tolerating multiple faulty regions. We also show that our scheme does not lead to deadlock with any combination of faults, while f-cube4 leads to deadlocks for some extreme combinations of fault regions.