Optical realization of a Clos nonblocking broadcast switching network with constant time network control algorithm.

The Clos interconnection network is one of the earliest multistage interconnection networks. Recently, a necessary condition on the number of middle-stage switches required to achieve broadcast capability was presented [Tech. Rep. JHU 90/04 (Computer Science Department, Johns Hopkins University, Baltimore, Md, 1990)]. A linear time control algorithm that determines whether a new input request is feasible or not was also provided. Here, the special characteristics of optics are used to provide a constant time parallel realization of the network control setup. This permits a reconfigurable Clos broadcast network.