Abstract: An error correction processing circuit, includes: a division circuit that divides input data into a plurality of pieces of a predetermined data length; a plurality of operation circuits that are provided in parallel, and that perform operations of error correction for the plurality of pieces of data divided by the division circuit, respectively; a multiplexing circuit that multiplexes the plurality of pieces of data for which the operations have been performed by the plurality of operation circuits; and an output circuit that outputs the data multiplexed by the multiplexing circuit.

Abstract: There is provided a node apparatus having a plurality of interface units for interfacing to a transmission line, switch units of a work system and a protection system for switching signals of the transmission line, and a service selector used to relieve a network failure over ring networks interconnected by node apparatuses, the node apparatus including a first controller for controlling the service selector in the switch units, and a second controller for controlling setting information of alarm detection in case of using the service selector in the interface units.

Abstract: An error correction processing circuit, includes: a division circuit that divides input data into a plurality of pieces of a predetermined data length; a plurality of operation circuits that are provided in parallel, and that perform operations of error correction for the plurality of pieces of data divided by the division circuit, respectively; a multiplexing circuit that multiplexes the plurality of pieces of data for which the operations have been performed by the plurality of operation circuits; and an output circuit that outputs the data multiplexed by the multiplexing circuit.

Abstract: A network apparatus includes: an input interface unit; a first and second line switching units cross-connecting output signals from the input interface unit; an output interface unit including a selection unit selecting outputs from the first or second line switching units; and a CPU. The line switching units each include: a control signal generation unit storing setting data in a memory and generating a line switching control signal based on the setting data; a memory error detection processing unit detecting a memory error and outputting error information; and a main signal processing unit writing setting data into a buffer when an error is not detected, and holding setting data stored in the buffer when the error is detected, and which performs cross-connection processing according to the setting data stored in the buffer. The CPU controls the selection unit according to the error information.

Abstract: An interface device for demultiplexing, from a first frame in a transport network, a plurality of second frames multiplexed into the first frame is provided. The interface device includes an extractor configured to extract a plurality of data groups to constitute the first frame, and a second frame generator configured to create the second frames based on the plurality of data groups extracted by the extractor.

Abstract: A network apparatus includes: an input interface unit; a first and second line switching units cross-connecting output signals from the input interface unit; an output interface unit including a selection unit selecting outputs from the first or second line switching units; and a CPU. The line switching units each include: a control signal generation unit storing setting data in a memory and generating a line switching control signal based on the setting data; a memory error detection processing unit detecting a memory error and outputting error information; and a main signal processing unit writing setting data into a buffer when an error is not detected, and holding setting data stored in the buffer when the error is detected, and which performs cross-connection processing according to the setting data stored in the buffer. The CPU controls the selection unit according to the error information.

Abstract: There is provided a node apparatus having a plurality of interface units for interfacing to a transmission line, switch units of a work system and a protection system for switching signals of the transmission line, and a service selector used to relieve a network failure over ring networks interconnected by node apparatuses, the node apparatus including a first controller for controlling the service selector in the switch units, and a second controller for controlling setting information of alarm detection in case of using the service selector in the interface units.