Hypercube connected rings: a scalable and fault-tolerant logical topology for optical networks

A new, fault-tolerant, scalable, and, modular virtual topology for lightwave networks employing wavelength division multiplexing is proposed. The proposed architecture is based on hypercube connected ring structure that enjoys the rich topological properties of hypercube, but it also overcomes one of its drawback. In a hypercube, the nodal degree increases with the number of nodes. Hence, the per-node cost of the network increase as the network size grows. However, in a hypercube connected ring network (HCR-Net) nodal degree is small and it remains constant, independent of the network population. HCRNet, like hypercube, is perfectly symmetric in the sense that average internodal distance in an N-node HCRNet is the same from any source node. Its average internodal distance is in the order of log N and it is comparable to other regular structures such as Trous and ShuueNet. HCRNet is based on the Cube Connected Cycle (CCC) interconnection pattern proposed for multiprocessor architectures. However, HCRNet improves on CCC by rearranging its hypercube links which results in a signiicantly lower average internodal distance. In this paper we present structural properties of HCRNet, and address the issues of scalability, and fast routing in complete as well as incomplete HCRNet.