Abstract: A k-source N1×N2 nonblocking multicast switching network has N1 input ports and N2 output ports with each port having k independent channels, in which each input channel can perform a multicast connection, i.e. send data simultaneously to multiple output channels, without interrupting existing multicast connections from other input channels. We provide the construction and the routing algorithm of a multi-source nonblocking multicast three-stage switching network. A k-source N1×N2 such a switching network consists of three stages of switch modules (which are k-source multicast switching networks with smaller sizes). It has r1 k-source n1×m switch modules in the input stage, m k-source r1×r2 switch modules in the middle stage, and r2 k-source m×n2 switch modules in the output stage with N1=n1r1 and N2=n2r2. There are exactly k channels (corresponding to one port of k-source switch module) between every two switch modules in two consecutive stages.

Abstract: Method and apparatus for performing group switching in DWDM optical networks are described. One embodiment is an N×N three-stage group connector with N inputs and N outputs, wherein the N outputs are divided into r output groups, each group including n outputs such that r=N/n. The group connector comprises a first stage comprising r n×m crossbar switch modules, wherein m?n?1; a second stage comprising m r×r crossbar switch modules; and a third stage comprising r M×N concentrator switch modules.

Abstract: Disclosed is a method for all-to-all personalized exchange for a class of multistage interconnecting networks (MINs). The method is based on a Latin square matrix corresponding to a set of admissible permutations of a multistage interconnecting network. Disclosed are first and second methods for constructing a Latin square matrix used in the personalized exchange technique. Also disclosed is a generic method for decomposing all-to-all personalized exchange patterns into admissible permutations to form the Latin square matrix for self-routing networks which are a subclass of the MINs.

Abstract: Disclosed is a method for all-to-all personalized exchange for a class of multistage interconnecting networks (MINs). The method is based on a Latin square matrix corresponding to a set of admissible permutations of a multistage interconnecting network. Disclosed are first and second methods for constructing a Latin square matrix used in the personalized exchange technique. Also disclosed is a generic method for decomposing all-to-all personalized exchange patterns into admissible permutations to form the Latin square matrix for self-routing networks which are a subclass of the MINs.

Abstract: A new self-routing multicast network that can realize arbitrary multicast (or one-to-many) communication without any blocking. Based on the binary radix sorting, all functional components of the network are recursively constructed reverse banyan networks using a self-routing procedure that provides for pipeline distribution of switch settings. The design allows a potential to greatly reduce the network cost by reusing part of the network. The new multicast network has O(n log2 n) cost (logic gates), O(log2 n) gate delay, and O(log2 n) set-up time, where the unit of time is a gate delay. Further, with feedback part of the network can be reused and the network cost is reduced to O(n log n).

Abstract: A controller for a nonblocking broadcast switching network comprising an input stage, an output stage, and a middle stage. The input stage has N.sub.1 or n.sub.1 r.sub.1 input ports and r.sub.1 switches, where n.sub.1 .gtoreq.2 and r.sub.1 .gtoreq.1 and are integers. The network also includes an output stage. The output stage has N.sub.2 or n.sub.2 r.sub.2 output ports and r.sub.2 switches, where n.sub.2 .gtoreq.2 and r.sub.1 .gtoreq.1 and are integers. There is also a middle stage. The middle stage has m switches, where ##EQU1## The m switches are in communication with the r.sub.1 switches and r.sub.2 switches. The middle stage of m switches has L inputs, where L.gtoreq.r.sub.1 and is an integer, and J outputs, where J.gtoreq.r.sub.2 and is an integer, corresponding to the n.sub.1 input ports and n.sub.2 output ports, x or fewer of the m switches, where 1.ltoreq.x.ltoreq.

Abstract: The present invention pertains to a nonblocking broadcast switching network. The network comprises an input stage. The input stage has N.sub.1 or n.sub.1 r.sub.1 input ports and r.sub.1 switches, where n.sub.1 .gtoreq.2 and r.sub.1 .gtoreq.1 and are integers. The network is also comprised of an output stage. The output stage has N.sub.2 or n.sub.2 r.sub.2 output ports and r.sub.2 switches, where n.sub.2 .gtoreq.2 and r.sub.1 .gtoreq.1 and are integers. There is also a middle stage. The middle stage has m switches where m is an integer and, where ##EQU1## The m switches are in communication with the r.sub.1 switches and r.sub.2 switches. The middle stage of m switches has L inputs, where L.gtoreq.r.sub.1 and is an integer, and J outputs, where J.gtoreq.r.sub.2 and is an integer, x or fewer of the m switches, where 1.gtoreq.x.gtoreq.min{n.sub.2 -1, r.sub.