Fujitsu Corporation

Hirotaka Morita

Koji Takeguchi

Nobuhiro Rikitake

Hideki Matsui

Ryuichi Moriya

Takuya Miyashita

Osamu Takeuchi

Yoshinobu Takagi

Chiyoko Komatsu

Hideaki Arao

Shinji Fukasawa

Hiroyuki Ohgaki

Ryuchi Moriya

Yuuji Kamura

Ken Mizukura

In order to increase the efficiency of large-capacity transmission, the continuity of divided signals generated by dividing a multiplexed signal is maintained and the original large-capacity multiplexed signal is restored. A signal dividing section divides a multiplexed signal to generate a plurality of divided signals in the STS or STM transmission interface format. A guarantee information adding section adds guarantee information for guaranteeing the continuity of the divided signals to each of the divided signals to generate transmission signals. A signal sending section sends the transmission signals via a transmission line in the transmission interface format. A signal receiving section receives the transmission signals. A signal restoring section restores the multiplexed signal by constructing the divided signals on the basis of the guarantee information.

Transmission system

When carrying out placement and routing processing on a layout object circuit using circuit connectivity information and power supply information, a first step of specifying a power supply terminal corresponding to a signal terminal designated for input level fixation by the circuit connectivity information on the basis of terminal correspondence information, a second step of specifying a power supply voltage corresponding to the power supply terminal specified at the first step on the basis of the power supply information, and a third step of routing a power supply line of the power supply voltage specified at the second step to the signal terminal for input level fixation and thus connecting them, are carried out. Thus, connection processing to connect the signal terminal for input level fixation and the power supply line can be automatically carried out and a design period for a multi-power supply semiconductor integrated circuit can be reduced.

Layout method for semiconductor integrated circuit, layout program for semiconductor integrated circuit and layout system for semiconductor integrated circuit

In a method for transmitting data from a first node to a second node through an interlinking network including data transmission equipments: the data is transmitted from the first node to one of the data transmission equipments together with a first request for storage of the data in the one of the data transmission equipments; the data is stored in a storage unit provided in the one of the data transmission equipments in response to the first request; a second request for the data is transmitted from the second node to the one of the data transmission equipments; the data is read out from the storage unit in response to the second request; and the data is transmitted from the one of the data transmission equipments to the second node.

Method and system for transmitting data in two steps by using data storage provided in data transmission equipment in network

A packet transmission system is disclosed. The system serves between terminal apparatuses that include a supervisory control circuit configured to transmit a supervisory signal in a direction opposite to the transmission direction of a main signal on each of and both of an upstream circuit and a downstream circuit. The packet transmission system transmits overhead information of a packet frame of the main signal of the upstream circuit and the downstream circuit using the supervisory control circuit of the downstream circuit and the upstream circuit, respectively.

Packet transmission system and a terminal apparatus

Disclosed herein is a SONET/SDH transmitter provided in a transmission system in which a SONET/SDH network and an IP network are connected with optical LAN-IF. The SONET/SDH transmitter has a redundancy transmission line structure consisting of two transmission lines, a K-packet processing section, and a transmitting section. The K-packet processing section is used for generating a specific byte (SONET K/Kbyte) of data representing transmission-line switching control information about the transmission lines, packetizing the generated data, and outputting a packet. The transmitting section is used for transmitting the packet to the transmitter provided opposite through the transmission lines. This SONET/SDH transmitter further has a redundancy line switching section. The redundancy line switching section is capable of selecting a transmission line, where a transmission signal with information data is transmitted, according to a status in which a packetized specific byte of data from the transmitter opposite is received.

Transmitter, SONET/SDH transmitter, and transmission system

A blade-type optical transmission apparatus includes a plurality of main-signal blades, each of which is provided with an external optical signal interface unit, a cross-connect unit, and an internal optical signal interface unit, a blade enclosure in which the plurality of main-signal blades are enclosed, and a back plane which is situated inside the blade enclosure and provides a ring connection for the internal optical signal interface unit between the main-signal blades.

Blade-type optical transmission apparatus

Proposed is an optical clock distribution system in the WDM network, which particularly relates to a system to control clock synchronization between optical transmission devices constituting an optical communication network. The optical clock distribution system includes an optical clock generator converting a clock signal of PRC (Primary Reference Clock) level into an optical clock signal having a wavelength &#x3bb;a wavelength multiplexer wavelength-multiplexing the optical clock signal having wavelength &#x3bb;together with other optical wavelength data; and a wavelength-demultiplexer provided in a unit of the network, wavelength-demultiplexing the optical clock signal having wavelength &#x3bb;wherein the other optical wavelength data are processed in the unit of the network using the wavelength-demultiplexed optical clock signal having wavelength &#x3bb;as a reference clock.

Optical clock signal distribution system in WDM network

A network synchronization controller and method for effectively preventing a timing loop from happening in a synchronous network. A clock status message controller, disposed in each network element on the network, produces and sends clock status messages which are each composed of clock quality data and synchronization control data. The clock quality data indicates the quality level of a clock signal that each network element supplies to its neighboring network elements. The synchronization control data contains information to be used to make the network synchronized with a single reference timing source. A clock selector chooses one of the clock signals received from other network elements, based on the clock status messages received along with the clock signals.

Network synchronization controller and timing loop prevention method

A wavelength division multiplexing transmission device includes a multiplexer part which multiplexes a plurality of first signals having a first bit rate and different wavelengths into a second signal having a second bit rate higher than the first bit rate and inserts wavelength data information concerning the different wavelengths into the second signal.

Wavelength division multiplexing transmission device and method having waveform discriminating function, and wavelength division multiplexing transmission system

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Kawasaki, Japan

Hirotaka Morita