The Augmented Composite Banyan Network

A new multipath multistage interconnection network called the Augmented Composite Banyan Network (ACBN) is proposed. The ACBN is created by adding a link to each SE of the Composite Banyan Network (CBN), which is a multipath network with at least two disjoint paths and was originally proposed in (Seo and Feng, 1995). Therefore, the basic building blocks in the ACBN are 4×4 SEs with log₂N stages. The ACBN inherits the favorable features of the CBN such as regularity, symmetry and easy rerouting capability under faults and conflicts. The ACBN also has an efficient and fast control algorithm that can easily generate a primary routing tag and alternative routing tags as in the CBN. A major improvement of the ACBN over the CBN is the higher connectivity with four disjoint paths between any source and destination pair. Moreover the ACBN can generate alternative routing tags in a much simpler way i.e., by a simple binary operation not by the conversion table as in the CBN. To compare the ACBN with other networks in connectivity, we introduce the definition of a degree of connectivity as a new connectivity measure function. The comparison results show that due to high connectivity the ACBN can resolve more random connection requests than other networks by using only a small amount of additional hardware