A new fault-tolerant network architecture: a composite banyan network

A new fault-tolerant architecture in multistage interconnection networks, called the composite banyan network, is proposed. The network is constructed by superimposing the reverse banyan network onto the banyan network. Basic building blocks in the composite banyan network are 3×3 switching elements (SEs) with log₂N stages. The major advantage of the composite banyan network over the existing networks with 3×3 SEs is an efficient and fast control algorithm to set up a path between any source and destination pair. Instead of complex numerical calculations, the network can easily generate a primary routing tag and alternate tags through simple binary operations. It is shown that there exist at least two totally disjoint paths between any source and destination pair, which increases the degree of fault tolerance. In order to increase the possibility of some frequently used permutations, a modified network is also proposed