Nested Multi-Connected Rings for Large High-Capacity LANs and MANs.

A multi-connected ring is a ring-structured network in which each node is also connected by chords to other nodes of the ring. The chords might be directed (modeling unidirectional transmission) or undirected (modeling bidirectional transmission). The span of a chord is the number of nodes counted between the endpoints of the chord (only one endpoint included). We define a multi-connected ring to be nested if it is rotationally symmetric and if the span of each chord is an integral multiple of the spans of each of the shorter chords. For local and metropolitan area networks, a Nested Multi-Connected Ring (NMCR) can be implemented as a multi-fiber ring network in which each node receives and transmits on a subset of the fibers in a bundle or cable. Because of the rotational symmetry, NMCRs have the especially attractive feature that an identical connector can be used at each node. A NMCR is one of several intermediary networks between a ring and a fully-connected network. Under a performance criterion that takes throughput, equipment cost, and complexity into account, an optimized NMCR outperforms both its extreme counterparts. Although ShuffleNet multi-connected rings can provide higher throughput per node than NMCRs, the rotational symmetry and identical connectors of NMCRs makes them preferable for applications with many nodes and lower throughput-per-node requirements.