Abstract: The present invention provides a communications system that improves upon the availability of communications paths between devices and simplifies the connectivity requirements to communicate data and control information to and from a remote station. System nodes are provided which are disposed along a time multiplex network signal stream. The nodes serve to interface remote stations to the network signal stream and may also switch information to different stations connected to the same node. The nodes are operative to allocate a variable bandwidth of the network signal stream for data communications between devices connected to different nodes. The nodes include switching devices that may be configured to accommodate stations that operate at different speeds. Allocation of bandwidth may be dynamically varied such that system resources are not unnecessarily diverted. Control of bandwidth allocation and internal switching within the node is accomplished via control information communicated to and from the node.

Abstract: A communications switching system is provided for transferring information between a plurality of node information highways (66,68) and between node information highways (66,68) and station ports (284,286), the system (221) comprising a plurality of switches (243) each switch having a station to highway section (244) and a highway to station section (246), each section (244,246) being in electrical communication with a station port (284,286) and with a plurality of node information highways (272,274). The station to highway section (244) and highway to station section (246) are each independently and dynamically configurable to communicate a selected bandwidth of information between the station ports and a selected node information highway. Each section (244,246) further being operative to serially integrate control information into the data stream communicated to the station port, and to derive control information from the serial signal stream received from the station port.

Abstract: A variable bandwidth branch exchange system is disclosed for interfacing a network ring to a plurality of peripheral loops, each of the peripheral loops being connected to one or more local stations and to a node on the network ring. Time bit slots on the network ring signal stream are assigned, on a dynamic basis, for communication between local stations. The network ring signal stream is diverted to the peripheral loop by the node when the bit slots assigned to the local station connected to that loop become accessible at the node, thereby placing the peripheral loop in the network ring signal stream. Bit slot bandwidth is variable in accordance with the requirements of a particular local station. Voice, data, and image communications are supported. The modular nature of the system permits the implementation of multiple rings for wide area networking.