Hitachi, Ltd.

Alaxala Networks Corporation

Takahisa Miyamoto

Toshikazu Yasue

Hidemitsu Higuchi

Ken Watanabe

Kazuaki Tsuchiya

Naoya Ikeda

Shinichi Hamamoto

Yoshifumi Atarashi

Munechika Sumikawa

Sunao Sawada

Makoto Kitani

Kazuko Iwatsuki

Yoshikazu Tominaga

Kenichi Sakamoto

Takeshi Aimoto

Koji Wakayama

Tatsuya Watanuki

Toru Horimoto

Yukio Shimamoto

Shinichi Akahane

Masaya Arai

Shinji Nozaki

Shuji Ohno

Hiroyasu Kimura

Norihiro Goto

Keiichiro Yamate

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 network management apparatus is previously registered with a physical connection relationship and positional information of a plurality of network relay apparatuses which form part of a network, as well as a configuration definition corresponding to the positional information, such that the network management apparatus can initially detect network relay apparatuses connected to the network management apparatus, and distribute a configuration definition, which takes into account a connection relationship, to the network relay apparatuses connected thereto to set the configuration definition in the network relay apparatuses in order. In this way, even if wiring is freely made, the configuration definition which should be set in each network relay apparatus can be appropriately distributed to and set in one adjacent network relay apparatus to another. Upon occurrence of a fault, the network can be appropriately recovered by a previously set recovering scheme.

Network operation management system

Enables control of data transmission within a network. For this, for example, a network relay apparatus makes a determination as to permission to transmit data, based on a condition relating to at least one of the transmission origin of the data and transmission destination of the data. An administration unit contains administration information indicating permission to use shared devices by users of clients. The connection relay apparatus for a target client acquires user identifying information from the target client. The administration unit acquires the user identifying information from the connection relay apparatus for a target client, and referring to the administration information, detects a target shared device that is one of the shared device permission to use of which has been granted to a user of the target client. The administration unit notifies the connection relay apparatus for the target shared device of permission for transfer of data between the target client and the target shared device, together with information identifying the target client. Upon receiving the notification, the connection relay apparatus for the target shared device sets the condition so as to change the data transmission permission between the target client and the target shared device from not authorized to authorized.

Data transmission control on network

A serverincludes a scenario table in which object to-be-monitored information that indicates one or more network devices A, B and C being objects for failure recovery, failure information for identifying contents of failures, countermeasure information against failures, and frequency information that indicates the number of times of the recoveries from the failures based on the countermeasure information are correspondingly stored. The network device Adetects the failure of the network device itself and transmits a failure event to the server. The serverselects the countermeasure information item in descending order of the frequency information items, by reference to the scenario table, and transmits the selected countermeasure information item to the network device A. The serverrepeats the selections and transmissions of the pertinent information item until the reception of the failure event from the network device Astops.

Failure recovery system and server

A handling address range is pre-assigned to each of switching devices consisting a network switching system. The switching device has a data receiving unit, an assigned data transport unit, an unassigned data transport unit, and a lower transport layer transport unit. The data receiving unit receives data including a destination address in a network layer and a destination identifier in a lower transport layer. If the destination identifier specifies the device itself, the assigned data transport unit and the unassigned data transport unit perform data transfer, whereas if the destination identifier specifies a device other than itself, the lower transport layer transport unit performs data transport. When the destination address is assigned address, the assigned data transport unit generates data including an identifier of a device corresponding to the destination address, and transports the generated data. When the destination address is not assigned address, the unassigned data transport unit transport the data to a switching device among the plurality of switching devices consisting the switching system to which the destination address is assigned.

Network switching system

In the case of detection of failure on a direct link interconnecting Master and Backup upstream switches, a control module of the Master upstream switch sends a partial failure message representing the occurrence of partial failure in the Master upstream switch via any of multiple lines connected to multiple ports of the Master upstream switch to the Backup upstream switch. Upon reception of the partial failure message from the Master upstream switch, a control module of the Backup upstream switch identifies partial failure occurring in the Master upstream switch and keeps the Backup operating status of the Backup upstream switch. Upon no reception of the partial failure message from the Master upstream switch, on the other hand, the control module of the Backup upstream switch identifies total failure occurring in the Master upstream switch and switches over the operating status of the Backup upstream switch from Backup to Master. In the event of failure occurring in the Master upstream switch, this arrangement effectively prevents unintentional interruption of data communication but ensures normal data communication in a network without causing the double-master state and the control loop in the network.

Network relay device for relaying data in a network and control method for the same

A first switch flashes an FDB upon receiving an FDB flash frame and then floods a multicast group join query message (QRY). A terminal sends a group join message (RP) back to the first switch. A second switch, a third switch and the first switch receive RPand perform IGMP/MLD snooping, respectively.

Switch and network fault recovery method

In a device that interworks a VLAN network and an MPLS network, a VLAN ID is associated with an MPLS label. In a device that performs interworking from a VLAN network to an MPLS network, an output MPLS label is determined from a pair of a VLAN ID and the information in the layer 3 or layer 4 header of a packet. The output MPLS label is assigned an independent value for each VLAN. In a device that performs interworking from the MPLS network to another VLAN network, the input MPLS label is associated with a VLAN ID.

Apparatus and method for interworking between MPLS network and non-MPLS network

A linking apparatus receives a first packet from a first network. When the first packet does not include a first header, a receiving section of the linking apparatus reads out a first header, which is stored after being associated with packet identification information having the same value as for packet identification information included in the first packet, from the stored first headers to output the first packet to which the first header is added. A sending section converts the first packet to a second packet to send the second packet to a second network.

Apparatus for linking a SAN with a LAN

In a device that interworks a VLAN network and an MPLS network, a VLAN ID is associated with an MPLS label. In a device that performs interworking from a VLAN network to an MPLS network, an output MPLS label is determined from a pair of a VLAN ID and the information in the layeror layerheader of a packet. The output MPLS label is assigned an independent value for each VLAN. In a device that performs interworking from the MPLS network to another VLAN network, the input MPLS label is associated with a VLAN ID.

Growing community of inventors

Kawasaki, Japan

Takahisa Miyamoto