Nonblocking conditions of multicast three-stage interconnection networks

This article considers three-stage switching networks able to support multicast traffic, that is, connections in which one inlet is connected to more than one output at the same time. The nonblocking conditions for this network are studied under the assumption of absence of any optimized routing of the connections inside the structure (the so-called strict-sense nonblocking networks). The theoretical nonblocking condition for such network under point-to-point traffic is the well known Clos condition. We give here the necessary and sufficient conditions for such network to be strict-sense nonblocking under multicast traffic. © 2005 Wiley Periodicals, Inc. NETWORKS, Vol. 46(4), 163–170 2005