Other

Hitachi, Ltd.

Hitachi Software Engineering Company, Ltd.

Yoshihito Sako

Takeshi Aimoto

Kazuo Sugai

Nobuhito Matsuyama

Takeki Yazaki

Tomohiko Tanabe

Hiroshi Sekino

Shinichi Akahane

Shigeki Morimoto

Masashi Fukuda

Nagayuki Hirota

Kazuaki Tsuchiya

Ken Watanabe

Jiro Kashio

Tetsuo Oura

Susumu Nakayashiki

Hiroyuki Wada

Hisashi Matsumura

Fumiaki Matsuura

Ihei Kajiya

Noboru Tanabe

A packet switching is performed according to a routing information for relaying particular packets which is produced by the route computation based on the information of a received packet and the kept parts-of-routing-information useful as a basis for the route computation. At this time, the route through which the packet is relayed is determined on the basis of the kept parts-of-routing-information before the route computation. Then, the received packet is relayed according to the determined route. Next, a new routing information is produced by the route computation based on the information of the received packet and the parts-of-routing-information. Thereafter, the succeeding packets of the same route are relayed on the basis of the new routing information.

Packet switching method and apparatus thereof

A network relaying apparatus and method for routing and transferring packets at high speed. A transfer engine stores the packets received through a network interface in a packet buffer, and stores the header information in a header RAM. A search engine searches the transfer control information including the transfer destination information and the action information in accordance with the header information, and writes it in the header RAM. The transfer engine produces an output packet based on the information stored in the packet buffer and the header RAM and outputs it to the transfer destination. A switch switches the output packet to the routing process of the destination. The transfer engine executes the receiving process and the transmission process, and the search engine executes the input search process and the output search process. Each of these processes is executed by pipelining control using a required table independently.

Network relaying apparatus and network relaying method capable of high-speed routing and packet transfer

The present invention improves a network forwarding device, such as a router, in a computer network system. When an address to which a received packet is to be forwarded is searched for based on path information, a path search data structure is changed to the one in which, in a 2-branch tree search in which a destination address of the received packet is checked, one bit at a time beginning at a highest-order bit, p (p is an integer equal to or larger than 2) levels are combined into one 2-branch tree to perform a search of the p levels of the 2-branch tree as a one-level search. This data structure speeds up path search processing.

Network repeater and network next transfer desitination searching method

In a high speed multicast route searching method of searching information of a transmission port to which a received multicast packet is next transferred: a route address is formed by coupling a receiver address and a sender address in this order; one p-th power-of-2-branch tree node is configured by a collection of one two-branch tree node and two-branch tree nodes of p&minus;1 stages totalling ((p-th power of 2)&minus;1) nodes just under the one two-branch tree node to form a p-th power-of-2-branch tree which is stored in a memory; not one bit but consecutive p bits of the route address coupling the receiver address and sender address in a received multicast packet in this order are checked at the same time; and in accordance with the values of the consecutive bits, a search tree stored in the memory is searched. In this manner, a search process can be completed by tracing nodes (the number of bits of a search key divided by p) times at a maximum, independently from the number of entries.

Packet relaying apparatus and high speed multicast system

A network relaying apparatus and a network relaying method for securing a high communication quality (QoS), a high reliability and security. A transfer engine stores the packets received through at least a network interface in a packet buffer, and the header information in a header RAM. A search engine searches for the transfer control information such as the destination information and the action information based on the header information, and writes them in the header RAM. The transfer engine prepares an output packet based on the information stored in the packet buffer and the header RAM, and outputs the output packet to the destination. A switch switches the output packet to the routing processor of the destination. Each header RAM is asynchronously accessible independently of the packet buffer and suppresses the competition for access between the transfer engine and the search engine.

Network relaying apparatus and network relaying method

A network relaying apparatus and method for high quality transfer of packets under stable quality-of-service (QoS) control. A transfer engine stores the packets received through a network interface, in a packet buffer, and the header information in a RAM. A search engine searches the transfer control information including the transfer destination information and the action information according to the header information and writes the resulting information in the header RAM. The transfer engine produces an output packet based on the information stored in the packet buffer and the header RAM and outputs it to the transfer destination. A switch operates to switch the output packet to the routing processor of the destination. The QoS control is performed at each of a plurality of points including the input-side routing processor, the output-side routing processor and the switch.

Network relaying apparatus and network relaying method capable of high quality transfer of packets under stable service quality control

A network relaying apparatus and method for detecting a flow at high speed and performing a variety of control operations including quality-of-service (QoS) control and filtering at high speed. A transfer engine stores the packet received through a network interface, in a packet buffer, and stores the header information in a header RAM. A search engine searches the transfer control information including the transfer destination information and the action information according to the header information, and writes it in the header RAM. The transfer engine produces an output packet based on the information stored in the packet buffer and the header RAM and outputs it to the transfer destination. A switch operates to switch the output packet to the routing processor of the final destination. A flow search table separates the action including the QoS corresponding to the packet source information and the transfer destination information by the input port number and searches for only an entry with a coincident input port number.

Network relaying apparatus and network relaying method capable of high-speed flow detection

An internetworking apparatus for interconnecting a plurality of networks, having forwarding sections corresponding to interfaces of the networks, each including a processor for performing packet forwarding processing and a statistics unit for collecting processing time statistics of the processor. An adjusting section connected to all the forwarding sections through a bus instructs each processor to change a program to be executed thereby based on the processing time statistics reported by each processor so as to balance processing loads on the respective processors.

Internetworking apparatus for load balancing plural networks

A method for performing a duplicated address test used for a network including a first ring transmission line, a second ring transmission line having a signal transmission direction opposite to that of the first ring transmission line, and a plurality of stations connected to at least one of these ring transmission lines. Each of these stations has a flag DAC representing whether or not the duplicated address test is performed, and some of the plural stations constitute a plurality of control nodes having a configuration function of the network. The flag DAC of each of the stations is reset at a time instant when a power source of this station is turned on, and also when any of the control nodes receives the sent out configuration control frame. Each of the stations having the reset flags DAC sents out the duplicated address test frame to either the first or second transmission line to which the station is connected when a token frame to control a transmission right is captured. When another station having the same address as that of a source station receives the test frame, a discriminator indicative of an address duplication is added to this test frame.

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Hadano, Japan

Yoshihito Sako