Alaxala Networks Corporation

Hitachi, Ltd.

Hiroki Yano

Shinichi Akahane

Kazuo Sugai

Keigo Uchizumi

Yuichi Ishikawa

Takeshi Aimoto

Yoshihiko Sakata

Takao Nara

Kaoru Okano

Kenichi Sakamoto

Nobuhito Matsuyama

Mitsuru Nagasaka

Hideki Hinosugi

Atsushi Anzai

Naoya Kumita

Tomohiro Baba

Yasuhiro Kodama

Nobuo Ogasawara

Yoshifumi Atarashi

Yutaka Takagi

Yoshinori Hachiya

Kentaroh Sugawara

It is an object of the present invention to achieve improvement of security by a whitelist function and improvement of network reliability by a network redundancy function at the same time. A packet relay deviceincludes packet reception units, a packet transfer unit, a S/W control unit, packet transmission units, and an input/output interfaceand automatically generates a whitelist including an allowed communication rule. It is possible to select whether to perform communication control using the whitelist or to carry out data communication without using the whitelist for each data reception unitthat receives data.

Communication device, system, and method

A communication apparatus receives control information of first data and a plurality of types of header information of first data, the first data being received by a first data receiver; selects a parameter from the plurality of types of header information of the first data based on a priority of a first data receiver group to which the first data receiver belongs and a storage condition, the priority being indicated by priority information, the storage condition indicating the number of entries of a whitelist that can be stored in a whitelist storage first memory; and add, to the whitelist, an entry that includes control information of the first data and at least one parameter selected above.

Communication apparatus to manage whitelist information

A network relay device includes a packet buffer for temporarily storing a received packet, and a packet buffer control section for changing an effective buffer number depending on the received amount of packet. When a traffic amount is small, the packet buffer control section reduces the power consumption by stopping the feeding of power or the supply of clock to a part of the packet buffers. The network relay device further includes plural table memories storing a table for deciding the transfer destination of packet, and a table memory control section for changing an effective table number according to a required number of table entries. When the required table entry number is small, the table memory control section reduces the power consumption by stopping the feeding of power or the supply of clock to a part of the table memories.

Network relay device and memory control method

A system having a plurality of network devices, each including: an interface module including a plurality of physical ports to transmit and receive packets; a computing module configured to execute a computing process with a computational expression using seed information, the seed information including at least one of destination information and source information associated with a received packet; a destination search module configured to, based on the result of the computation, select a physical port for transmission of the received packet from a plurality of candidate ports among the plurality of physical ports; and a modifying module configured to modify the computational expression, wherein the plurality of network devices include preceding-stage and subsequent-stage network devices, the subsequent-stage network device being directly coupled to the preceding-stage network device with physical wiring, and wherein the subsequent-stage and preceding-stage network devices are configured to use different expressions in the computing process.

Device and method for relaying packets

A packet relay device is equipped with a buffer memory including a plurality of queues for temporarily storing packets, and a storage unit for storing the first queue lengths indicating the respective queue length of each of the queues and a second queue length indicating a value according to a total of the plurality of first queue lengths. When the packet relay device receives packets, it discerns the queue to which the received packet belongs from among the plurality of queues, and temporarily stores the packet in relation to the discerned queue within the buffer memory. Then, the first queue length and the second queue length are updated, and a determination is made of whether or not to send a congestion notification to the packet sending source according to the first queue length corresponding to the discerned queue, and to the second queue length.

Packet relay device and congestion control method

Computing process with a computational expression is executed using seed information including at least one of destination information and source information associated with a received packet. It is preferable to select a physical port for transmission of the received packet based on the result of the computation. It is also preferable to select a port group for transmission of the received packet based on the result of the computation. Here, the computational expression is capable of being modified. Meanwhile, the physical port for transmission of the received packet is selected from a plurality of candidate ports among the plurality of physical ports. The port group for transmission of the received packet is selected from among a plurality of port groups including a mutually different candidate port.

A network switching device includes multiple ports, multiple switching processors, and a table manager. The switching processors respectively have an address table, a output port specification module, an update requirement determination module, and a table update module. The output port specification module refers to a destination address in received data and the address table and specifies a output port for sending the data among the multiple ports. The update requirement determination module determines requirement for update of the address table with regard to a source address in the data. The table manager has an update detail acquisition module and an update request module. Upon determination of the requirement for update of the address table, the update detail acquisition module obtains an update detail of the address table from one of the switching processors. The update request module sends an update request to the switching processors, based on the update detail.

Network switching device and control method of network switching device

Packets are relayed using a network relay device including a plurality of interface units. Each of the interface units includes one or more physical ports for connection to a line, and a bandwidth controller configured to control transmission bandwidth for packets received by the physical ports. Furthermore, a single specific physical port is selected as the output physical port from the distributed-control logical port based on output port group information unique to the output port group including the distributed-control logical port.

The present invention provides a technology for processing packets, such as VoIP packets, with priority. A priority-designating unit designates priority information based on header information. A pointer searching unit refers to a pointer table to obtain pointer information corresponding to a destination address. A sorting unit sorts the pointer information into a high-priority queue and a low-priority queue according to the priority information. A next queue holds pointer information obtained from a destination information table. A scheduler extracts and outputs the pointer information from each queue in the following order of priority: the next queue, a high-priority queue, and a low-priority queue. A destination-information-table searching unit obtains destination information and/or the pointer information from the destination information table based on the pointer information, and outputs the destination information to a packet forwarding and duplicating unit and outputs the pointer information to the next queue.

Packet forwarding apparatus and method for multicast packets

In one embodiment, a bandwidth monitoring device comprises a packet receiving circuit configured to receive packets; a counter configured to count a total packet length by adding up inputted packet lengths including a packet length of a next input packet and subtracting outputted packet lengths to produce a counted value; a timer configured to time a packet receiving time; a memory configured to store a number of packet receiving times and a number of counted values counted by the counter which correspond to the packet receiving times, respectively; a counter rate-of-change calculating portion configured to calculate a change rate by a first counted value corresponding to an oldest packet receiving time stored in the memory representing an oldest time at which a packet was received and a second counted value corresponding to a latest packet receiving time stored in the memory representing a latest time at which a packet was received; and a determining portion configured to decide whether the next input packet will be discarded based on a probability computed by the change rate and the counted value counted by the counter when the packet receiving circuit receives the next input packet.

Bandwidth monitoring device

A packet routing apparatus has a routing information table comprised of a plurality of sub-tables. Each sub-table includes an entry of a first format indicative of routing information, and at least one of the sub-tables includes, in addition to the entry of the first format, an entry of a second format for designating another sub-table to be referred to. A routing processor of the packet routing apparatus refers to a sub-table designated by an input line interface. As a result, when the entry of the second format is retrieved, the routing processor executes routing of an input packet and header conversion by referring to another sub-table designated by the entry.

Packet routing apparatus and routing controller

A traffic shaping apparatus calculates a minimum transmission interval, an allowed transmission frame rate of a user frame, and a reference transmission interval for each user according to a minimum transmission frame rate and a peak transmission frame rate specified for each user. The traffic shaping apparatus also calculates a first estimated transmission time according to the reference transmission interval, and a second estimated transmission time according to the minimum transmission interval for each user. The traffic shaping apparatus determines the user having the earliest first estimated transmission time, and determines according to the second estimated transmission time of the user whether a user frame is to be transmitted.

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Toyota, Japan

Hiroki Yano