Abstract: An apparatus for use in a optical fiber ducting system, the apparatus including a housing; a first aperture in the housing, the first aperture being arranged to receive a multi-bore optical fiber duct including at least two bores; at least two further apertures in the housing, the further apertures each being arranged to receive a respective optical fiber duct; and at least one connection means for connection of an individual bore of the multi-bore duct to at least one of the respective fiber ducts.

Abstract: A local telecommunications network system IS arranged to provide a first asymmetric digital subscriber line (ADSL) service in a first frequency band to a first set of subscribers and a second very high bit rate digital subscriber line (VDSL) service in a second frequency band higher than the first frequency band to a second set of subscribers. Interference between the two types of digital traffic within the multi-pair feeder cables leading to the exchange is suppressed by low pass filtering the ADSL traffic and high pass filtering the VDSL traffic. The filtering may be applied to the line cards to which each subscriber line is connected.

Abstract: A passive optical network having a plurality of optical splitters/combiners each comprising first and second through ports and at least one drop port. The through ports of the plurality of splitters/combiners are concatenated to form a linear arrangement having two end through ports. Optical signals may be transmitted between the end through ports by means of the linear arrangement; and signals may be transmitted between at least one of the end through ports and one of the drop ports by means of the linear arrangement. The splitter/combiners can be inserted to form drop points in a ring or dual-homed passive optical network to provide flexibility in provision of protection and network reconfiguration.

Abstract: A Hall effect device is employed in telephone exchange circuitry for detecting when a called subscriber goes off-hook. This is done by detecting when a DC current due to line looping is superimposed on the AC current due to ringing whereupon ring trip occurs. Also described are circuits in which after ring trip has taken place the Hall device continues to supervise the called line loop.

Abstract: A Hall effect device is employed to monitor the presence and direction of line current flow. The output of the Hall effect device is fed to an amplifier having a known output level for a zero input. The output of the amplifier will increase or decrease dependent on the direction of the current flow. The output of the amplifier is monitored for change and direction of change of current flow.