Abstract: A network over which a medium is transferred. The network includes S core rings. Each core ring can be modeled as a set of nodes interconnected by links, where S is greater than or equal to 4 and is an integer, each said core ring having at least N nodes, where N is greater than or equal to 4 and is an integer. Each node/link is configurable in terms of directing the medium from a given source toward a given destination, and where each of the core rings is directly connected by means of k spanning links, where k is greater than or equal to 2, so as to comprise a spanning ring to at least a second and a third of the other core rings. The combinations of core rings spanned by each core ring is such that there is a path comprised of links and nodes from each node on any core ring to any other node on any other core ring. A method for transferring a medium.

Abstract: A network over which a medium is transferred. The network includes S core rings. Each core ring can be modeled as a set of nodes interconnected by links, where S is greater than or equal to 4 and is an integer, each said core ring having at least N nodes, where N is greater than or equal to 4 and is an integer. Each node/link is configurable in terms of directing the medium from a given source toward a given destination, and where each of the core rings is directly connected by means of k spanning links, where k is greater than or equal to 2, so as to comprise a spanning ring to at least a second and a third of the other core rings. The combinations of core rings spanned by each core ring is such that there is a path comprised of links and nodes from each node on any core ring to any other node on any other core ring. A method for transferring a medium.

Abstract: The present invention pertains to a conferencing network. The conferencing network is comprised of a ring array comprised of K conferencing modules, where K is greater than or equal to 3 and is an integer. The K conferencing modules are capable of being in desired states. The conferencing network also includes means for controlling the ring array such that the conferencing modules are placed in the desired states. Switching stages comprised of switches can also be implemented into the conferencing network.

Abstract: A rearrangeable fully available multistage switching network having N.sub.T inputs and M.sub.T outputs, preferably where N.sub.T =M.sub.T, comprising a plurality of switching elements arranged in an array of .theta. stages, where .theta..gtoreq.3. The inner groups of stages define a plurality of nested modules where each of the switches in an outer stage is connected to associated subordinate inner modules such that at least one set, f.sub.i, of said connections between stages is redundant, that is, greater than 1.