Fujitsu Corporation

Junichi Kawaguchi

Koji Hachiya

Masakazu Sato

Yasuyuki Mitsumori

Kenichi Okabe

Kanta Yamamoto

Satoru Saitoh

Tetsuo Ehara

Katsumi Imamura

Yuichiro Katsura

Yoshiyuki Karakawa

Yuji Kuroki

Masaki Bansho

Hiroshi Ishiwata

Seishiro Taniguchi

Hiroko Yoshino

A packet processing apparatus includes a plurality of communication connecting unit each connected with a communication partner apparatus using one of a work path and a protection path, connecting unit for connecting, using a data bus, the plurality of communication connecting unit with one another; determination unit for, when a packet sent from the communication partner apparatus is received by one of the communication connecting unit, determining whether the packet is a maintenance packet that is used for monitoring a connection state with the communication partner apparatus; and transmitting unit for, when it is determined that the packet is a maintenance packet by the determination unit, transmitting the maintenance packet to the plurality of communication connecting unit using the data bus via the connecting unit.

Packet processing apparatus, interface unit and method thereof

When a ringlet with a high frame transfer quality is selected as a switching candidate for each station of a transfer destination from information on frame transfer quality for each ringlet, when it is determined that a fundamental ringlet is in a preceding stage of degradation of the frame transfer quality from information on the frame transfer quality of the fundamental ringlet, and if the fundamental ringlet is different from the switching candidate, a ringlet for transferring a frame to a station of the transfer destination is switched from the fundamental ringlet to the switching candidate.

Method, apparatus, and computer product for switching ringlets

A signal distribution method and a signal distribution apparatus are disclosed, wherein transport packets of a television signal containing multiplexed channels are provided in a transmission format of a digital broadcasting standard, and such transport packets are transmitted and distributed over a synchronous network. Transmission rate (data speed) of the transport packets of a given customer in the synchronous network is selectable based on the number of multiplexed channels for the customer.

Signal distribution method and a signal distribution apparatus

An ATM switching system concentrates cell streams, which are output by respective ones of a plurality of line interfaces, by a concentrator, enters a resulting cell stream into an ATM switch unit, deconcentrates cells, which have been switched by the ATM switch unit, by a deconcentrator on a per line interface basis and sends the cells to lines. Each line interface converts a VPI/VCI included in the header of a cell that has entered from a line to an internal cell address having a number of bits smaller than the number of bits of the VPI/VCI. Each unit in the ATM switching system performs management of various data and controls cell switching based upon a converted cell address without relying upon the VPI/VCI. The line interface restores an internal cell address, which is included in the header of a cell that enters from the side of the ATM switch, to the VPI/VCI and sends the cell to a line.

ATM switching system

Growing community of inventors

Fukuoka, Japan

Junichi Kawaguchi