| 摘要 |
An optical bypass switch for a fiber optic local area communications network (LAN) with a ring topology allows an optical signal carried on the ring to by pass a node, which includes terminal equipment and a stub cable, associated with the switch. In a non-bypass mode, the optical signal is transmitted to and from the associated terminal. The switch assembly is remote from its associated terminal and includes optical couplers and associated optical receivers and activity detectors to produce electrical signals indicative of an optical input to and output from the terminal. Logic circuitry analyzes these signals and produces an appropriate drive signal for a switch controller. The remote switch has a local power supply and is preferably located at the junction of the ring and an associated, purely dielectric stub cable. The terminal can include a dual path transceiver and bridging equipment to provide cross links between terminals in the event of a link failure to complement the node failure protection of the bypass switch.
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