Patent ID: 7058084

Claim:
A multistage interconnect network comprising: (a) a plurality of switch nodes connected together, each of the switch nodes comprising a first plurality of input ports selectively connectable to a second plurality of output ports, the multistage interconnect network comprising more than ┌log b N┐ stages of switch nodes, wherein b is a total number of switch node input/output port pairs, N is a total number of network input/output port pairs, and ┌log b N┐ indicates a ceiling function providing the smallest integer not less than log b N, the stages thereby providing a plurality of paths between any network input port and network output port to enhance fault tolerance and lessen contention; (b) the multistage interconnect network including forward channel and back channel signal paths between the switch nodes; (c) the multistage interconnect network capable of multicast transmitting forward channel messages from a source connected to the multistage interconnect network to one or more destinations connected to the multistage interconnect network; (d) the multistage interconnect network capable of combining back channel replies received from the destinations into a single result, wherein the result is transmitted on the back channel to the source.