Fujitsu Corporation

Katsuhiro Shirai

Koji Takeguchi

Yasuko Nozu

Takashi Honda

Masahiro Shioda

Masakazu Bamba

Junichi Moriyama

Kanji Naito

Tetsuya Uchida

Toshihiro Togo

Hayato Furukawa

Mineshi Nakashima

A transmission device includes: a payload generator configured to generate a payload; and an adding unit configured to add payload information on the payload to the payload, wherein the payload to which the payload information is added is transmitted via a first lane, and management information on the first lane is transmitted via a second lane.

Transmission device, transmission system, and transmission method

A noise suppression method is used in an optical transmission system which includes node equipments transmitting a WDM optical signal. First node equipment drops a first optical signal from the WDM optical signal. The method includes: transmitting a failure signal that specifies the first optical signal from second node equipment to the first node equipment via a first route when the second node equipment arranged on the first route for transmitting the first optical signal to the first node equipment has detected a failure of the first optical signal; transmitting a shutoff signal that specifies the first optical signal from the first node equipment toward the second node equipment via the first route; and shutting off an optical output of a wavelength corresponding to the first optical signal in third node equipment that has relayed the failure signal and has received the shutoff signal.

Optical transmission system and noise suppression method

A node device in an optical transport ring network including plural node devices connected in a ring form using plural optical transmission paths so that optical transport frames of a working line and a protection line are transmitted using the plural optical transmission paths, includes a control information transmitter, when a failure occurs in the optical transmission paths, transmitting the optical transport frame to an opposing node device as a transmission destination node in the optical transmission paths, the optical transport frame including switching control information; and a switcher receiving the optical transport frame including switching control information, the optical transport frame being transmitted to the node device as the transmission destination node, forming a loop back to fold a transmission path between the plural optical transmission paths, and switching the optical transmission path from the work line to the protection line.

Method of switching optical transport network and node device

A communication apparatus operable to set a path based on path setting information used to set a communication path over a communication network formed by a plurality of the communication apparatuses, the communication apparatus including a first storage medium operable to store first path setting information formatted with a first format, a second storage medium operable to store second path setting information formatted with a second format, and a controller operable to control to convert control information of the communication apparatus in which the first path setting information stored in the first storage medium is set, to the second path setting information formatted with the second format.

Communication apparatus and path setting control method

There is provided a communication device including a score information storage unit to store score information indicating a score as an evaluated value of a communication path; a receiver unit to receive a route connection notice including current score information; a routing unit to acquire the score information stored in the score information storage unit, and select the communication path next to the communication path based on the acquired score information of the communication path; a score updating unit to add a score of the communication path selected by the routing unit to the current score of the partial communication route indicated by the current score information, and update the current score information to the added score as a new current score; and a transmission unit to transmit the route connection notice including the current score information.

Communication device, system and method to form communication route

A network connection device for performing a process of transmitting and receiving a SONET/SDH frame includes a first protocol processor which processes a first network management protocol; a second protocol processor which processes a second network management protocol; a frame header extractor which extracts a header from the received SONET/SDH frame; and a protocol identifier which identifies a network management protocol based on the extracted frame header. The network connection device selects one of a control signal outputted from the first protocol processor and a control signal outputted from the second protocol processor based on a result of the identification, and outputs the control signal.

Network connection device and signal processing method in the network connection device

In an optical amplifying technique using remote pumping, an optical transmitting apparatus and an optical repeating apparatus are provided. An optical repeating apparatus comprises a first optical transmitting unit, a first loopback unit, a second optical transmitting unit, a second loopback unit, and four optical couplers, wherein transmission light and reception light are transmitted through one optical fiber cable, whereby the installation cost and maintenance cost of the optical cable are decreased. Disconnect of the optical cable is detected by a monitoring function using pumping light and residual pumping light, whereby reliability and safety of the system are remarkably improved. Additionally, adjustment of the optical output level of the repeating station can be most suitably set according to an actual transmission distance.

Optical transmitting apparatus and optical repeating apparatus

The present invention relates to a wavelength division multiplex optical transmission apparatus including an optical sending system having at least a plurality of optical sending sections to generate and transmit optical signals having different wavelengths &lsqb;hereinafter referred to as optical signals&rsqb; , a plurality of optical amplifying sections to amplify the optical signals, and a wavelength division multiplexing section to process by wavelength division multiplexing the optical signals after optical amplification. An optical output level control section is mounted in the apparatus to control, for the wavelengths, optical output levels of the optical signals output to the optical transmission line through the wavelength division multiplexing section by individually varying amplification factors of the optical amplifying sections in the optical sending system. It is thereby possible to adjust, for the wavelengths, send optical output levels of the optical signals having the plurality of different wavelengths, to be transmitted after the wavelength division multiplexing so as to transmit, for the wavelengths, the optical signals at optimal optical output levels.

Wavelength division multiplex optical transmission apparatus

A first transmitting unit provided in a first station transmits a first optical signal to a second receiving unit provided in a second station via an optical transmission line, the first optical signal including first overhead information. A first receiving unit provided in the first station receives a second optical signal transmitted from a second transmitting unit provided in the second station via the optical transmission line, the second optical signal including second overhead information. A first inserting unit inserts first data for detecting line-disconnection troubles into the first overhead information, the data inserting being performed without causing a data amount of the first overhead information to be increased, contents of the first data for detecting line-disconnection troubles being different from contents of second data for detecting line-disconnection troubles being inserted into the second overhead information by a second inserting unit provided in the second station. A first extracting unit extracts the data for detecting line-disconnection troubles from the overhead information included in an optical signal received by the first receiving unit, the data for detecting line-disconnection troubles being either the second data for detecting line-disconnection troubles if the second optical signal has been received by the first receiving unit or the first data for detecting line-disconnection troubles if the first optical signal has been received by the first receiving unit as a result of returning.

Optical bidirectional transmission system and method having

A transmission device includes an exciting light source outputting an exciting light, a first optical part which supplies an optical amplifying part with a signal light and the exciting light, a second optical part which supplies an amplified light to an optical transmission line and receives a light received via the optical transmission line, and a control part which determines whether the light received includes the exciting light output by the exciting light source and controls the exciting light source to stop outputting the exciting light.

Transmission device connected to optical transmission line

An optical line switch device which contains: an optical switch which can input a transmission optical signal which is to be transmitted through one of first and second optical transmission lines, first and second optical coupling and branching units which can be connected with the first and second optical transmission lines, respectively, and an optical coupling unit which can output an input optical signal which is input from one of the first and second optical transmission lines. The transmission optical signal is supplied to one of the first and second optical coupling and branching units according to a switch control signal which is applied to the optical switch when the optical switch inputs the transmission optical signal. One of the first and second optical coupling and branching units transmits the transmission optical signal on one of the first and second optical transmission lines connected thereto when the transmission optical signal is supplied thereto. When one of the first and second optical coupling and branching units inputs an optical signal as the input optical signal, the input optical signal is suppled to the optical coupling unit. The optical coupling unit outputs the input optical signal when the input optical signal is suppled thereto.

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Kawasaki, Japan

Katsuhiro Shirai