Nonblocking self-routing switching networks

The authors investigate a class of binary self-routing switches, characterized by the way they function. These switches can describe for example the functional aspects of some recently developed self-routing photonic switches. First the authors show that, within this class, essentially they only need to consider the four possible types of fixed-directory routing switches. Then the authors determine exactly the minimum number of switches contained in an M-input N-output wide-sense nonblocking self-routing network composed of switches from this class.