A RECURSIVE CONCENTRATOR STRUCTURE WITH APPLICATIONS TO SELF-ROUTING SWITCHING-NETWORKS

A technique for constructing an N-input concentrator from two (N/2)-in put concentrators and a stage of 2x2 switching elements is described. Recursive decomposition of each of the (N/2)-input concentrators yield s a log2N-stage switching network similar in topology to the inverse o mega network. The control algorithm for setting the switching elements is shown to be a simple logic function of the activity bits of the in puts. An iterative cell that combines the functions of the control log ic and the 2x2 switching element can be used as a building block to re alize the entire concentrator. Applications of the concentrator struct ure as an interconnection fabric in fast packet switching is explored. This leads to an efficient self-routing network, similar in topology to the transposed Batcher-banyan network.