Nippon Telegraph and Telephone Corporation

Nec Corporation

Hitoshi Irino

Hirokazu Tohya

Noriaki Ando

Akira Matsuda

Hiroshi Wabuka

Aki Fukuda

Masaru Katayama

Takayoshi Hirasawa

Yoshinori Koike

Transfer apparatuses perform communications for path control with a centralized control apparatus that performs centralized control from the outside of a switch cluster including the group of transfer apparatuses, through a path similar to D-plane (main signal). A packet flow controller serving as a separation unit that separates a packet for the inside of the cluster and a packet for the outside of the cluster transmitted through the similar path from each other, and an internal route engine that performs path control of obtaining a path for freely passing through a plurality of paths in the cluster are provided. The packet flow controller separates a path control packet for the inside of the cluster, and the engine performs, when a failure to communicate the path control packet for the inside thus separated occurs, path control of generating a path that bypasses a path with the failure.

Transfer device, transfer system, transfer method, and program

A tunnel connection is enabled between a user terminal and a service provider using a simpler network configuration. A communication systemincludes a user terminal, a service provider, a carrier networkthat connects the user terminaland the service providerto each other, and a network control devicethat controls the carrier network. The network control devicesets respective virtual tunnel end points (VTEPs) for a POI terminalthat is on the carrier networkand that is connected to the service providerand for the user terminal, and sets a virtual tunnel between the virtual tunnel end points. The user terminalcommunicates with the service providervia the virtual tunnel.

Network control device, user terminal, communication system, network control method, and network control program

A network system in which network relay devices such as switches or routers which reduce the load of VPN path information are connected to a Clos topology and a configuration method thereof are provided. A network system according to the present invention is a network system in which a plurality of network relay devices that are routers or switches are connected by a leaf/spine type Clos topology and which performs path control using BGP. Each of the plurality of network relay devices belongs to an entire AS made up of all of the plurality of network relay devices by BGP confederation, and the respective network relay devices belong to a sub AS. A leaf type network relay device is connected to a spine type network relay device via an eiBGP peer and is connected to the other leaf type network relay devices via as iBGP peer.

Network system and configuration method therefor

Monitoring for preventative maintenance using Simple Network Management Protocol (SNMP) polling suitable for a large scale network is realized. A controller of the present invention for use in a system that monitors a plurality of monitored apparatuses by SNMP polling includes a request duplication unit that duplicates an SNMP request from an operator terminal, and a request transmission unit that transmits the duplicated SNMP requests to the monitored apparatuses all at once. The controller includes a response calculation unit that calculates an operator response value from a response value of the monitored apparatus which is retained in an apparatus information database (DB) according to a monitoring policy retained in a monitoring policy DB.

Relay device and relay 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

A method for designing a decoupling circuit for a source line of a LSI includes the steps of determining the capacitance of the decoupling capacitor based on the electric charge necessary for one cycle operation of the LSI and the allowable fluctuation of the source voltage, and determining the inductance of the source line based on the impedance of the decoupling capacitor and the allowable minimum multiplexing ratio of the source current by the decoupling capacitor.

Method for designing a decoupling circuit

A design support system according to the present invention comprises: an LSI library , in which rated characteristics of various LSIs are stored by an LSI library preparation unit ; a decoupling capacitor library , in which rated characteristics of various capacitors are stored; a PCB library , in which the cross-sectional structures of various power wiring lines are stored; a decoupling capacitor search unit , for employing the LSI library and the decoupling capacitor library ; a power wiring determination unit , for employing the results obtained by the decoupling capacitor search unit , the LSI library and the PCB library ; and a design results output unit , for outputting the results received from the power wiring determination unit . Furthermore, the data in the three libraries can be updated or new data can be added.

Method for designing a power supply decoupling circuit

A minute shielded loop probe is built in the vicinity of the terminal of the IC socket. The IC is fixed to the IC socket and driven by the external power source and the external signal, and thereby a magnetic field generates in the vicinity of the terminal of the IC by the high frequency current flowing through this terminal. It is possible to obtain the high frequency current flowing through the terminal on the magnetic field. With this procedure, it is possible obtain the high frequency current accurately and easily, and then to take effective measures against EMI.

IC socket

Protection circuits for preventing an internal circuit on a semiconductor substrate from destroying due to an excess voltage are formed on the output end and input end of an internal circuit. The protection circuit on the input end has a gate electrode comprised of a band-like conductive film. This gate electrode is grounded and has a shape zigzagging in a waveform with crests and troughs alternately appearing in a planar view. A drain diffusion layer connected to an output end of the internal circuit is formed in one of two diffusion regions of the surface of the semiconductor substrate that are defined by the gate electrode, and a source diffusion layer grounded is formed in the other region. The source diffusion layer and the drain diffusion layer are formed integral with each other, so that the protection circuit on the input end is substantially constituted of one buffer transistor.

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Tokyo, Japan

Hitoshi Irino