Fujitsu Corporation

Hiroshi Kinoshita

Atsuko Higashitaniguchi

Satsuki Norimatsu

Takahiro Suetsugu

Kunihiko Hamamoto

Takashi Hatano

Daisuke Nagai

Shinichi Hayashi

Masami Doukai

Yoshihiro Shimizu

Shigeru Suzuyama

Akira Tokunaga

Noriki Kajizaki

Tsuyoshi Takehiro

Colin Peters

Takanori Choumaru

Ayako Hashimoto

Takahiro Akatsuka

Kazuhiko Inada

Shingo Suzumori

The disclosed apparatus includes a MAC learning table storing a MAC address and port identification information that uniquely identifies a port for transferring a frame to which the MAC address is assigned. The apparatus includes updating the MAC learning table, reading a MAC address of a link trace frame, transferring the link trace frame via a port determined based on the MAC learning table, storing a correspondence relationship of a predetermined MAC address and port identification information, saving a correspondence relationship set as an object to be deleted at a time of updating the MAC learning table, transferring the link trace frame, if there is no correspondence relationship relevant to the MAC address of the link trace frame in the MAC learning table, and sending a response frame to a switching hub which is an originator of the link trace frame with transfer of the link trace frame.

Link trace frame transfer program recording medium, switching hub, and link trace frame transfer method

A data relay device includes a plurality of transmission ports that constitutes a logical port, and stores therein a MAC learning table and a CoS distribution table. The data relay device reads a MAC address and a CoS value from a frame, and reads a logical-port ID corresponding to the MAC address from the MAC learning table. The data relay device reads a transmission-port ID corresponding to the logical-port ID and the CoS value from the CoS distribution table, and outputs the frame to a transmission port indicated by the transmission-port ID. On the transmission port, the frame is stored in a transmission queue corresponding to the CoS value, and the frame is transmitted at a shaping rate assigned to the transmission queue.

Data relay device, data relay method, and computer product

In a data transmission method and apparatus which can perform a switchover of all of the main lines without requiring much construction cost, a transmission apparatus sets, upon frame transmission or reception, combinations of a plurality of main lines with virtual paths established so as to include at least a part of a bandwidth of the main lines in one or more protection lines as redundant configurations. Upon frame transmission, the apparatus copies frames received in the main lines, assigns identifiers of the redundant configurations to the copied frames, and transmits the copied frames to the virtual paths of the redundant configurations. Upon frame reception, the apparatus determines whether the main lines or the virtual paths forming the redundant configurations are valid, deletes the identifiers of the redundant configurations assigned to frames received from the protection lines, and determines whether the frames from which the identifiers have been deleted should be respectively discarded or transferred depending on validity or invalidity of the main lines.

Data transmission method and apparatus

The present invention provides a carrier network in which a spanning tree with no loops can be constructed even in a dual homing configuration, and a communication method for a control frame. By allocating an identical virtual network identifier to a plurality of user networks connected to the carrier network, a single virtual network is constituted. An ingress communication node connected to a first user network of the plurality of user networks attaches a tag including the virtual network identifier to a control frame transmitted from the first user network, and transmits the control frame attached with the tag to a transmission destination determined on the basis of the virtual network identifier. An egress communication node connected to a second user network of the plurality of user networks receives the control frame attached with the tag, which is to be transmitted to the second user network, removes the tag from the control frame attached with the tag, and transmits the control frame to the second user network.

Carrier network of virtual network system and communication node of carrier network

A transfer system for bundle transfer, in which the amount of route information and the number of times advertisement is performed are reduced, and maintenance and management are made to be highly efficient to implement improved transfer quality. A path setting section specifies a path between nodes for a receiving side as a bundled link which can have a plurality of paths tied up. A transmission-side route-information advertisement section advertises route information in a network when recognizing that the path has been established. A path recognition section recognizes the path and sets the path as a bundled link. A receiving-side route-information advertisement section advertises the route information in the network when recognizing that the path has been established.

Transfer system

A resilient packet network (RPR) device is connected to one or more rings to constitute an RPR network. The RPR device has a storage unit in which a correspondence between RPR device addresses, each indicating an RPR device connected to the one or more rings, and user device addresses, each indicating a user device accommodated in the RPR device, is stored. When the RPR device receives data addressed to a predetermined user device from a user device accommodated in the RPR device itself, if an RPR device address of an RPR device accommodating the predetermined user device is registered in the storage unit, an RPR header, in which the RPR device address is set as a destination RPR device address, is added to the data. The data with the RPR header is transmitted to the RPR network.

Resilient packet ring device

In a network providing a wide-area LAN service which allows communications to be performed between user networks () via a carrier network (), edge switches () each comprise: a tentative learning registration means () which, when a packet whose source MAC address and receiving port are not yet learned is received from the carrier network, registers the source MAC address and the receiving port in a tentatively learned state; a learned state changing means () which changes the learned state of the destination MAC address of a packet received from an associated one of the user networks to a permanently learned state; and a permanent learning registration means which, when a packet whose destination MAC address is registered in a learned state is received from the carrier network, registers the source MAC address and receiving port of the packet received from the carrier network in a permanently learned state. The invention thus provides a MAC address learning apparatus that improves the hit rate in a MAC address learning table maintained in each of the edge switches () provided in a wide-area VLAN carrier network.

MAC address learning apparatus

A traffic engineering method is provided for optimizing an entire network resource, to a network divided intro a plurality of areas, each area including a plurality of nodes. According to the traffic engineering method, a load-balancing process is performed in each area separately. Thus, a memory capacity required by a node carrying out the load-balancing process can be reduced by a large amount, thereby achieving a high-speed load balancing process.

Traffic engineering method and node apparatus using traffic engineering method

When setting up a working path, a protection path is automatically set up by taking each node on the working path as a start point. A working path setup request message carrying 'protection needed/not-needed' information is transmitted from an ingress node toward an egress node along the route of the working path. When transferring a path setup response message as a response to it, each node autonomously determines the route of the protection path and sends out a protection path setup request message along the route of the protection path.

Method and apparatus for protection path setup

A route bypassing a root node is constructed in a network in which a spanning tree is formed. A received frame is sent out on a designated port as well as on a root port by using a designated-port data send-out function, provided that a transmitting port for the received frame is learned on the root port. When a frame is received on a blocking port, a transmitting port for a frame whose destination matches the source address of the received frame is temporarily learned on the blocking port by using a blocking-port learning function, on the condition that the destination of the received frame is already learned on some other port. When a frame whose destination matches the temporarily learned address is received, the temporary learning is changed to normal learning by using a temporarily learned address-based data transfer function.

Spanning tree bypassing method and apparatus

Disclosed is a method of avoiding a collision of a frame and enabling the guarantee of the QoS in a network using the CSMA/CD system, wherein when a terminal transmits a frame onto a transmission line, timing information as to the timing of transmitting a next frame is added to the frame. All the terminals in the same segment reserve the timing information in timing reservation management tables respectively, as the timing of transmitting a frame from other terminal, and prohibit the transmission of frames from their own terminals. In addition to that, each terminal reserves the timing of transmitting a next frame from its own terminal in a timing reservation management table, and when the timing comes, it transmits a next frame onto the transmission line.

LAN interface apparatus and a method of controlling the transmission and reception of a frame

The present invention relates to a high-speed digital transmission method using an analog subscriber line (for example, an existing telephone-use copper cable), a subscriber accommodating system used in the high-speed digital transmission method, an accommodating device on a subscriber-terminal side and an accommodating device on an accommodating station side. The present invention includes the steps of providing a subscriber distributing device, to which a plurality of subscribers are connected, on a subscriber-terminal side of an analog subscriber line in a high-speed digital transmission method using the analog subscriber line; setting a low-frequency band part as a control channel; setting a high-frequency band part as one or a plurality of communication channels; and controlling the one or plurality of communication channels by use of the control channel. The plurality of subscribers communicate by using the same analog subscriber line.

Growing community of inventors

Fukuoka, Japan

Hiroshi Kinoshita