Fujitsu Corporation

Masanori Kondo

Toshihiro Ban

Takashi Fukagawa

Masayuki Ono

Kazuhiro Minamimoto

Kazuhiro Ohnuma

Toshihide Tsuzuki

Yasushi Nishine

Shogo Sawamura

An apparatus includes a first port coupled to a first apparatus through a ring line, a second port coupled to a second apparatus through a second line, the second apparatus disposed external to the ring line, the second line configured redundantly with a first line between the first apparatus and the second apparatus, a third port coupled to the first apparatus through a control line for a control signal concerning the first line, and circuitry that detects a fault in the control line, wherein the circuitry detects a fault in the second line, switches the second line from an active line to a standby line in accordance with the detection of the fault in the second line, and while the fault in the control line is detected, shuts down the first port in accordance with the detection of the fault in the second line.

Communication apparatus, communication system, and communication control method

A disclosed communication apparatus of one embodiment of the present disclosure includes a transmitting unit including a counter for counting the number of transmitted data frames and indicating the counted number of the transmitted data frames as a counter value and a scheduler for determining a frame transmission order, and configured to transmit one or more data frames and a monitoring and control frame which includes the counter value; and a generating unit configured to generate the monitoring and control frame. When generating the monitoring and control frame, the generating unit corrects the counter value included in the monitoring and control frame according to the frame transmission order.

Communication apparatus and OAM frame transmission method

According to an aspect of an embodiment, a node apparatus used in at least part of nodes in a network formed by a plurality of nodes coupled in the shape of a ring, comprising: a working node function performing unit for performing functions as a working apparatus that selectively drops a frame destined for a terminal hosted by the node itself among frames transmitted on the ring and adds a frame from the terminal hosted by the node itself to frames transmitted on the ring; a back-up function performing unit for performing functions as a back-up apparatus that lets a frame destined for a terminal hosted by the node itself pass through to an adjacent node and discards a frame from the terminal hosted by the node itself; and a function selection unit for selectively enabling one of the working node function performing unit and the back-up function performing unit.

Ring node apparatus

An apparatus for transmitting terrestrial digital data using a synchronous-optical-network system or a synchronous-digital-hierarchy system includes a synchronous-difference calculating unit that calculates a synchronous difference between a standard signal used in the synchronous-optical-network system or the synchronous-digital-hierarchy system and a first synchronous signal that synchronizes with a leading position included in image data of the terrestrial digital data; and a transmission processing unit that transmits the synchronous difference together with the terrestrial digital data to a destination.

Growing community of inventors

Kawasaki, Japan

Masanori Kondo