Abstract: A fiber optic cable assembly with enhanced flexibility and reduced installation cost in contrast to conventional multiple duct systems. The fiber optic cable assembly comprises a central innerduct adapted to provide a pathway for installing conventional cable by pulling of the cable therethrough. A plurality of air blown fiber (ABF) tubes are positioned around the circumference of the central innerduct for installing air blown optical fiber bundles therethrough, and a plurality of strength elements are provided around the circumference of the central innerduct and interposed among the plurality of air blown fiber (ABF) tubes. A layer of water-blocking material is provided between an outer jacket and the air blown fiber (ABF) tubes and strength members.

Abstract: A method of automatically determining an attached device type for a multi-port LAN switch, and configuring the port based on the attached device type is provided. The method comprises setting a LAN switch port to a port mode, and determining, during a first period of time, whether an attached device is attempting to insert at the LAN switch port. If the attached device is attempting to insert during this first period of time, the method continues by configuring the LAN switch port in the port mode. If the attached device is not attempting to insert during the first period of time, the method continue by setting the LAN switch port in an adapter mode, transmitting a test frame to the attached device, and then determining, during a second period of time, whether a response frame is received from the attached device. If a response frame is received during the second period of time, the method further includes configuring the LAN switch port in the adapter mode.

Abstract: A ring network of workstations interconnected on a single simplex ring is converted to duplex communications on the single ring by placing two transceivers in each workstation and adding a duplex conversion device between each workstation and its ring terminal box. One of the transceivers receives and retransmits signals in a clockwise direction around the ring; the other transceiver receives and retransmits signals in a counter-clockwise direction around the ring. The clockwise and counter-clockwise signals are superimposed on the ring but are isolated at the workstations by the duplex conversion device.

Abstract: A station in a communications network determines the mode (full-duplex or half-duplex) in which it communicates with a concentrator port by establishing a Registration routine between the station and the concentrator port. The station and concentrator port exchange frames which disclose the capabilities of the concentrator port. If the concentrator port has duplex capabilities, the station enters as a duplex station. Otherwise, the station enters in a half-duplex (token ring) mode.

Abstract: A wiring methodology for attaching office machines to a communications network includes at least one central wiring facility or concentrator with lobe segments emanating or fanning out in a "Star Fashion" configuration to terminal points within offices. A plurality of switch control elements are provided in the concentrator. When activated, each switch control element inserts a lobe segment and attached machines into the communications network. Lobe segments not in use are bypassed (disconnected) within the concentrator. A single station connector (SSC) can be used to increase the number of office machines that may be attached to a single lobe segment. In addition, the SSC may be used to configure a mobile Local Area Network (LAN) System without resorting to permanent wiring schemes.

Abstract: A device, method and system for testing in situ the wiring between a data terminal equipment and a ring or similar type local area network having a loop conduction path with a plurality of data terminal equipment (DTE) coupled to said loop conduction path. The DTE is provided with a mechanism for generating d.c. current. The d.c. currents flow from the DTE through a length of interconnecting conductors and self-shorting connectors towards the loop conduction path. Current measuring devices monitor the current at the interconnecting conductors for imbalance current flow and/or over current. The presence of either a current imbalance and/or over current indicates a malfunctioning (short circuit, broken wire, etc.) in the wiring.

Abstract: A relay driver circuit, suitable for controlling a bistable relay, includes a storage device which is charged to a first voltage level by a low current flow voltage source. A first switching circuit couples the storage device to the bistable relay when the first voltage level exceeds a predetermined value. The charge on the storage device is dumped into the relay and forces it into a first state (set). A second switching circuit is coupled to sense the voltage on the storage device and the voltage on the low voltage source. When the voltage on the low voltage source falls below the voltage on the storage device, current flows from the storage device and forces the relay into a second state (reset). The reset time is within 100 .mu.s.

Abstract: A relay driver circuit, suitable for controlling a bistable relay, includes .[.a storage device which is charged to a first voltage level by a low current flow voltage source..]. .Iadd.a transformer which handles both an information signal and a control signal and a storage device. The control signal is provided by a low current low voltage source. .Iaddend.A first switching circuit couples the storage device to the bistable relay when the first voltage level exceeds a predetermined value. The charge on the storage device is dumped into the relay and forces it into a first state (set). A second switching circuit is coupled to sense the voltage on the storage device and the voltage on the low voltage source. When the voltage on the low voltage source falls below the voltage on the storage device, current flows from the storage device and forces the relay into a second state (reset). The reset time is within 100 .mu.s.