Reduction of crosspoints in one-sided crosspoint switching networks

Abstract

In this paper, we establish upper and lower bounds for the number of crosspoints required in a one-sided crosspoint switching network to provide a given level of connectivity. Two modes of operation are considered, namely nonblocking and rearrangeable. A complete nonblocking switch matrix with N ports has JVV2 crosspoints. We show that this number can be reduced by at most N/2 - 1 crosspoints for nonblocking operation. If rearrangeable operation is allowed, however, as many as 25 percent of the crosspoints can be removed. We analyze the relationship between the number of crosspoints removed and the maximum number of rearrangements of connections needed. We also introduce algorithms for rearrangement of connections in both single-chip and partitioned implementations with reduced number of crosspoints. © 1989 IEEE.