Hitachi, Ltd.

Hitachi Communication Systems, Inc.

Haruo Shibata

Koji Tanaka

Koji Hirayama

Yutaro Asano

Takahiko Kozaki

Susumu Matsui

Yukiko Takeda

Hidenori Inouchi

Noboru Endo

Masahiro Hayashi

Mika Mizutani

Kiyoshi Aiki

Takumi Oishi

Shinichi Iwaki

Keisuke Shirai

Akio Kawase

Toshiya Ouchi

A translation apparatus retains a first correlation between a Mobile IPv6 terminal's home address and virtual IPv4 address. When the Mobile IPv6 terminal transmits a packet to said IPv6 network with a care-of address specified as the packet's source address and a home address specified in an extension header, the translation apparatus changes the packet's source address to a virtual IPv4 address that corresponds to the packet's home address in accordance with the first correlation, and then transmits the packet to an IPv4 network. Mobile IPv6 terminal-to-IPv4 terminal communication can then be established between an IPv6 network to which Mobile IPv6 terminals are connected and an IPv4 network to which IPv4 terminals are connected.

Method and apparatus for translating protocol

A method of relaying data between a first terminal device connected to a first network and a second terminal device connected to a second network comprises: searching in a storing device based on location information accompanying data received from the first terminal device or the second terminal device, the storing device storing location information indicative of a location of at least the first terminal device; as a result of the searching, if the location information exists in the storing device, converting the location information accompanying the data so that the location information stored in the storing device becomes a new location information of the data; and sending the data accompanied with the location information having been converted to the second terminal device or the first terminal device.

Method and device for data relaying

A service of reducing the number of tunnels in exchange for a specified service fee. A communication system, which generates tunnels in physical lines and multiplexes a plurality of sessions on the physical lines, comprises a monitor unit for monitoring the state of use of tunnels and sessions used by the user when the user using a plurality of tunnels is a customer who requires service of reserving sessions in a smaller number of tunnels in exchange for a specified service fee; a tunnel/session control unit performs control so as to gather the plurality of sessions of said user in a specified tunnel when the sessions currently used by the user can be reserved in a smaller number of tunnels; and a charging unit for charging a usage rate according to the number of tunnels or the number of physical lines used.

Communication system, a communication method and communication terminal

An IPv6 mobile packet communication network in which mobile VPN service can be provided without having to use a mobile tunnel. A control signal for enabling packet data transmission and reception is sent from a mobile terminal to a gateway node. Using destination-of-connection information contained in the control signal, the gateway node checks whether mobile VPN service is requested or not. Upon detection of a mobile VPN service request, the gateway node returns IP address information of the gateway node to the mobile terminal via a subscriber node. The mobile terminal then assembles an IPv6 header () and an IPv6 routing header () so that packet data will be unexceptionally transferred through the gateway node.

Mobile communication network, terminal equipment, packet communication control method, and gateway

A switching system for realizing integration of existing communication networks or interconnections thereof, and a switching control method. After a call is originated from an ATM communication networkto an STM communication network, an ATMIFthat has received a connection request signal (control signal) converts the control signal into a format of an ATM cell, adds a header destined to one of SIG-to n for processing control signals, and then output the same. An ATMSWperforms self-routing based on header information. The selected one of the SIG-to n performs conversion for the ATM cellby a specified protocol, makes an ATM cellhaving a header destined to one of CLP-to k for processing control signals, and then output the same. Upon having received the ATM cell, the CLPlinks up with other processors to perform call connection control, functions having been dispersed among the other processors.

Switching system and switching control method

A plurality of packet gate ways (PGWS) are connected between a mobile communication system and an internet so that the corresponding IP subnetworks to those PGWs may be built. A visitor location register (VLR) operates to notify the PGW of location information of the mobile station (MS) and an IP address of a data terminal connected with the MS. If the notified IP address belongs to another IP subnetwork, the PGW notifies the corresponding PGW to that IP subnetwork of a fact that the local PGW is a destination. The PGW operates to manage the location information of the MS connected with the data terminal based on the notified content and perform the packet routing based on the managed content.

Mobil communication system for providing IP packet communications and method for routing IP packets

In a shared-buffer-type ATM switch including a multiplexer, a shared buffer memory, a demultiplexer, a buffer memory controller, a cell copy section is disposed between the multiplexer and the memory. The copy section produces a plurality of copies of a broadcast cell according to information of a copy information table and adds associate routing information to each copied cell so as to write the cells in the memory. In response to an indication from an output counter, the cells are read from the memory to be distributed to output ports, thereby implementing a broadcast function.

Growing community of inventors

Yokohama, Japan

Haruo Shibata