Comments on "An optimal shortest-path routing policy for network computers with regular mesh-connected topologies"

S. Badr and P. Podar (1989) introduced a zig-zag routing policy and showed its optimality for shortest-path routing on square or infinite grid networks with independent link failures. This paper shows that, contrary to the claim of Badr and Podar, a zig-zag policy is not optimal for shortest-path routing on torus networks.<
>