Nippon Telegraph and Telephone Corporation

Ntt Advanced Technology Corporation

Masaru Katayama

Akira Misawa

Satoru Okamoto

Eiji Oki

Toshiya Matsuda

Kana Masumoto

Masahiro Nakagawa

Yuta Ukon

Toru Homemoto

Kenji Tanaka

Takeshi Sakamoto

Naoaki Yamanaka

Tsuyoshi Ito

Kazuyuki Matsumura

Naoki Miura

Yuki Arikawa

Kohei Shiomoto

Wataru Imajuku

Hitoshi Irino

Hidetoshi Onda

Kyota Hattori

Naoki Kimishima

Akihiko Miyazaki

Katsutoshi Koda

A data transfer device transfers a received packet. If the transfer destination of the received packet is a data processing device under control, the data transfer device (confirms the state of a shared bus, and if the shared bus is usable, transfers the packet to the data processing device of the transfer destination via the shared bus, gives the use right of the shared bus to one of the data processing devices in response to communication requirements from the data processing devices, and receives, via the shared bus, a packet from the data processing device given the use right.

Data transfer device, data processing device and data processing method

A data acquisition device includes a valid data acquirer configured to acquire valid data from communication data based on an analysis parameter including an offset from a head of the communication data to the valid data and a data length of the valid data and output the acquired valid data.

Data acquisition device and data acquisition method

An object is to provide a dispersion compensating system with a large amount of dispersion compensation and reduced operation costs. Disclosed is a dispersion compensating system in which a core node and an access node are connected through a ring network, the access node includes a delay measurement unit configured to receive delay measurement signals from the core node to measure a delay between the core node and the access node, an average dispersion amount calculation unit configured to calculate an amount of dispersion compensation to be applied to an optical burst signal prior to transmission to the ring network, based on the delay thus measured, and a real-part inverse dispersion application unit configured to perform pre-equalization on a waveform of the optical burst signal prior to the transmission, based on the calculated amount of dispersion compensation.

Dispersion compensation system and dispersion compensation method

[Problem] To allow addition of new functions to an optical module at a low cost. [Solution] An optical transceiverincludes a CPUconfigured to perform download control of a program for executing an additional function to be newly added to the optical transceiver, a wireless transmitting and receiving deviceconfigured to receive, in accordance with the download control, the program from a terminal devicethat stores various programs, and a memory unitconfigured to store the program that is received. The CPUis configured to perform, by interrupting a monitoring and control signal from a transmission device, control to write data related to transmission and reception processing of a Txand a Rxin accordance with execution of the programs stored in the memory unitin a storage area at a specific address of an EEPROM

Optical transceiver

An optical transmitter generates two modulated optical signals by modulating two optical carriers respectively with two binary bit sequences by on-off keying and generates an orthogonal polarization multiplexed optical signal from the two modulated optical signals. The two optical carriers respectively have peak frequency components spaced apart from each other by a predetermined frequency difference and located such that a central frequency of a WDM channel of a WDM grid falls between the peak frequency components. An optical receiver separates the orthogonal polarization multiplexed optical signal into two signals in which components of the two modulated optical signals are combined with different combination ratios, by means of a 1-input, 2-output asymmetric filter whose two optical transmittances intersect at the WDM grid and each have a free spectral range equal to or twice the channel spacing of the WDM grid, and restores the two modulated optical signals from the separated two signals using a DSP.

Optical transmitter, optical receiver, and optical transmission system

An optical network system includes a master node and a plurality of optical switch nodes, allowing the number of nodes without depending on the number of wavelengths. The master node is configured to: divide a wavelength path having an arbitrary wavelength into time slots each having a predetermined time period; and allocate the time slots to each of the optical switch nodes. Each of the optical switch nodes is configured to: synchronize the time slots based on information delivered from the master node; and thereby transmit or receive a data or performs route switching.

Optical network system, optical switch node, master node, and node

An economical optical network is constituted by effectively using network resources by using the minimum number of, or minimum capacity of 3R repeaters. 3R section information corresponding to topology information on the optical network to which an optical node device itself belongs is stored, and the 3R section information stored is referred so as to autonomously determine whether or not the optical node device itself is an optical node device for implementing the 3R relay when setting an optical path passing through the optical node device itself. Alternatively, when the optical node device itself is a source node, another optical node device for implementing the 3R relay among the other optical node devices through which the optical path from the optical node device itself to the destination node passes is identified, and this identified optical node device is requested to implement the 3R relay when setting an optical path in which the optical node device itself is a source node.

Optical node device, network control device, maintenance-staff device, optical network, and 3R relay implementation node decision method

A Flow Record restriction apparatus is provided for restricting a transmission number of Flow Records while maintaining measurement information of the whole traffic. The Flow Record restriction apparatus includes: a flow generation unitconfigured to determine a set of packets having the same attribute to be a flow of the same communication, and to generate a Flow Record based on header information of the packets for each flow; a Flow Record number restriction function unitincluding a management buffer for temporarily storing generated Flow Records, and being configured to read the Flow Records from the management buffer and output the Flow Records; and a Flow Record transmission unitconfigured to packetize the output Flow Records to transmit packets over the measurement network, wherein, when a number of Flow Records stored in the management buffer exceeds a preset upper limit value, the Flow Record number restriction function unitaggregates a part of stored Flow Records.

Flow record restriction apparatus and the method

An OVPN user register an L1 signal type information which is used in the user's device in an OVPN terminating device in advance together with an IP address and a VPNID which are allocated to the user's device. Registered contents are notified to other OVPN terminating devices which control the same VPNID as that of the user's device. Otherwise, when a calling connection request arrives from the user's device, the registered contents are notified other OVPN terminating devices which control the devices which receive the notification. By doing this, it is possible to handle a request by the user for changing the setting for the signal format which is employed in the user's device quickly. Also, it is possible to realize an OVPN which can perform a process for a calling connection request from the user efficiently and improve an operability for the user.

OVPN system, OVPN terminating device, collective controlling device, and optical communication network

The invention relates to a node, an optical/electrical path integrated network using this node, and a program which controls the node. The node according to the invention is suited to use in an optical/electrical path integrated network constructed from a plurality of electrical sub-networks comprising nodes which are interconnected by electrical paths in which routing is performed based on packet header information and a photonic core network comprising nodes which are interconnected by optical paths, the photonic core network and the plurality of electrical sub-networks being interconnected by optical paths, wherein the node comprises a device which outputs to other nodes, a traffic quantity between the node to which it belongs and other nodes.

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Tokyo, Japan

Masaru Katayama