Lower bounds for WSNB multi-log/sub 2/N switching networks

Multi-log/sub 2/N switching networks are one of the propositions for high-speed and high-capacity electronic and photonic switches. These networks have recently been studied for strictly nonblocking and rearrangeable nonblocking operations in the case of unicast connections. Wide-sense nonblocking conditions of these networks were considered only for multicast connections. Lower bounds for wide-sense nonblocking conditions of multi-log/sub 2/N switching networks with unicast connections are considered. For some algorithms, the required number of planes is the same as in strict-sense nonblocking switching networks. We also prove, that, for switching networks with an odd number of stages, the lower bound for wide-sense nonblocking operation is greater than the necessary and sufficient conditions for rearrangeable switching networks.