Group switching for DWDM optical networks

A new class of interconnection networks called group connectors are introduced. A group connector G(N, n) is a switching network that consists of N inputs and N outputs such that (1) its N outputs are divided into N/n groups with n outputs in each group, and (2) it can provide any simultaneous one-to-one connections from the N inputs to the N outputs, possibly without the ability of distinguishing the permutation of the outputs within each group. Note that a group connector is able to distinguish among groups of outputs. Group connectors has applications in the switching matrices in dense wavelength-division multiplexing (DWDM) networks. Clearly, an N × N permutation network can be used as an N × N group connector. We show that a group connector can be built at a lower hardware cost than that of a permutation network of the same size.