Fault Tolerant Token Ring Embedding in Double Loop Networks

Abstract A double loop network G(n; s1, s2) is a digraph with n nodes 0, 1, …, n − 1 and 2n links of the form i → i + s1 (mod n) and i → i + s2 (mod n). A double loop network G(n; s1, s2) is LFT if there is a Hamiltonian cycle in every G(n; s1; s2) − e where e is any link in the network. Similarly, a double loop network G(n; s1; s2) is NFT if there is a Hamiltonian cycle in every G(n; s1; s2) − v where v is a node in the network. In this paper, we present necessary and sufficient conditions for LFT and NFT double loop networks, respectively.