Hitachi, Ltd.

Alaxala Networks Corporation

Tokyo Shibaura Electric Co., Ltd.

Ken Watanabe

Kazuaki Tsuchiya

Naoya Ikeda

Shinichi Hamamoto

Toshikazu Yasue

Hidemitsu Higuchi

Takahisa Miyamoto

Yoshifumi Atarashi

Munechika Sumikawa

Masaya Arai

Manabu Fujita

Kensuke Ino

Tatsuya Watanuki

Susumu Hashimoto

Kazuo Sugai

Sunao Sawada

Shinji Nozaki

Tetsuo Oura

Yoshihito Sako

Tokuhiro Niwa

Etsuji Suzuki

Atsushi Maeda

Kazuko Iwatsuki

Katsuyoshi Onishi

Tomio Kashihara

Yoshitaka Sainomoto

Shohei Fukuzaki

Tsuyoshi Kodama

Yuuki Inujima

Kazutomo Kon

Kenji Ishida

Kazuko Ito

Hisaaki Shibata

A Provider Edge PEreplicates a received packet and relays these to virtual circuits VC, VCrespectively, and Provider Edges PE, PErespectively receive the packets from the virtual circuits VC, VC, whereupon the Provider Edges PE, PE, on the basis of an agreement between them, decide to handle the received packets such that one of the first edges relays the packet to a Customer Edge CEfor forwarding to a Host A, while the other edge discards the packet without relaying it to the Customer Edge CE

Data communication system and method for preventing packet proliferation in a multi-device link aggregation network

Network repeaters which each implement a redundant switching function previously grasp connection states of ports of a network system by using an inquiry frame and an exchange frame. At the time when a line is broken, when actively confirming a state of a port connected to a port in which a line is broken via a downstream device, the network repeaters each grasp that which portion of the line is broken and determine whether a switchover is required. Through the process, the network repeaters each prevent a useless switchover such as switching-back immediately after the switchover, and at the same time since a mechanism of waiting for a given length of times is not required, they each perform a fast switchover.

Redundant control device and network system

In an apparatus, there are provided an IP transmitting and receiving unit for transmitting and receiving an IPv4 packet and an IPv6 packet; an IP header converting unit for performing a mutual conversion of the IPv4 packet and the IPv6 packet by an IP header conversion; a DNS substituting unit for receiving a domain information capturing request sent from an IPv4 terminal or an IPv6 terminal and substituting its process; an IPv4 address capturing unit for capturing an IPv4 address from a DHCP server; and an IP address conversion information holding unit for holding an IPv6 address of the IPv6 terminal and the IPv4 address captured by the IPv4 address capturing unit in correspondence to each other. Thus, a communication with the IPv4 terminal can be executed without preliminarily fixedly allocating the IPv4 address to the IPv6 terminal.

Communicating method between IPv4 terminal and IPv6 terminal and IPv4-IPv6 converting apparatus

A translator for coupling a first IPv4 network and a second IPv6 network having different addressing architectures for IP addresses so as not to exhaust the IP addresses of one of the two networks, a network system using the translator, and a network coupling method. When a packet is transferred from the IPv6 network to the IPv4 network, the translator assigns any of previously prepared IPv4 addresses to an IPv6 address stored in a source storing field of the IPv6 packet. The assigned address is stored in a source storing field of an IPv4 packet. A packet translation unit assigns the foregoing IPv6 address to an IPv4 address stored in a destination storing field of the IPv4 packet, when a packet is transferred from the IPv4 network to the IPv6 network, and stores this address in a destination storing field of the IPv6 packet.

Translator for IP networks, network system using the translator, and IP network coupling method therefor

When the provider edge PEdetects the occurrence of a failure at the access line AL, it sends the label withdraw message to the virtual circuit VC, and when the provider edge PEreceives the label withdraw message sent via the virtual circuit VC, the access line ALis put to a link down state, and when the customer edge CEdetects the link down state of the access line AL, it switches from the normal path to the redundant path.

Data communication system, device and method of detecting a failure on an access line in a network

Data communication system and method for preventing packet proliferation in a multi-device link aggregate network

A packet communication method and a packet communication system capable of making an IPv4-compatible application operating on an information processing apparatus communicate with another information processing apparatus connected to an IPv6 network without using an address translation router. In the information processing apparatus connected to the IPv6 network, an IPv4-to-IPv6 protocol conversion control function is incorporated in a LAN driver. A protocol conversion control module receives an IPv4 packet from a protocol control module. When a send destination IPv4 address contained in a header of the packet is registered in an address translation table incorporated in the protocol conversion control module, an IPv6 address is generated to be sent onto a LAN. Unless the send destination IPv4 address contained in the packet header is registered in the address translation table incorporated in the protocol conversion control module, the IPv4 packet as received is intactly sent onto the LAN.

Packet communication method and apparatus and a recording medium storing a packet communication program

A packet communication apparatus sends an authentication request packet received from a user terminal to an authentication server. If a packet received from the authentication server is an authentication packet for the user terminal, an authentication controller executes authentication processing of the authentication packet. If the authentication packet includes connection limit information for the user terminal, a connection limit controller sets the connection limit information to the user terminal. According to the connection limit information, the packet communication apparatus sends the packet received from the user terminal to a quarantine server disposed to quarantine the user terminal.

Packet communication apparatus

A Provider Edge PEreplicates a received packet and relays these to virtual circuits VC, VCrespectively, and Provider Edges PE, PErespectively receive the packets from the virtual circuits VC, VC, whereupon the Provider Edges PE, PE, on the basis of an agreement between them, decide to handle the received packets such that one of the edges relays the packet to a Customer Edge CEfor forwarding to a Host A, while the other edge discards the packet without relaying it to the Customer Edge CE

A packet communication method and a packet communication system capable of making an IPv4-compatible application operating on an information processing apparatus communicate with another information processing apparatus connected to an IPv6 network without using an address translation router. In the information processing apparatus connected to the IPv6 network incorporates, an IPv4-to-IPv6 protocol conversion control function is incorporated in a LAN driver. A protocol conversion control module receives an IPv4 packet from a protocol control module. When a send destination IPv4 address contained in a header of the packet is registered in an address translation table incorporated in the protocol conversion control module, an IPv6 address is generated to be sent onto a LAN. Unless the send destination IPv4 address contained in the packet header is registered in the address translation table incorporated in the protocol conversion control module, the IPv4 packet as received is intactly sent onto the LAN.

Growing community of inventors

Kawasaki, Japan

Ken Watanabe