Hitachi, Ltd.

Hirofumi Masukawa

Tomohiro Baba

Junnosuke Wakai

Taketoshi Kawashima

Kazumi Hakuta

Shiro Ohtani

Hisanori Kimoto

Hitoshi Yoshida

Norihiko Moriwaki

Kazuma Yumoto

Kazuhiro Kusama

Takuro Mori

A failure detection protocol is applied so that failure detection requests for the same aggregated link can be processed even when the failure detection requests differ among routing protocols. The failure detection protocol is executed for each of the physical links that form an aggregated link, and a notification is sent to a higher-level application (for example, a routing protocol), which is a requesting source of a communication line failure monitoring request, with a discrimination between a case in which the communication of the aggregated link in its entirety fails and a case in which some physical links of the aggregated link fail.

Network system and node apparatus

When any communication port receives a packet from a network, it transmits the packet to a relay processing section. The relay processing section identifies a relay processing section of a transfer destination according to destination information included in the packet to transmit the packet to a packet switch section. When the relay processing section of the transfer destination is a working relay processing section, the packet switch section transfers the packet to the working relay processing section and a protection relay processing section.

Packet routing apparatus and a method of communicating a packet

Disclosed is a packet communication apparatus of large capacity capable of realizing high throughput and packet priority control in packet switching for changing connection of input and output ports of a switch on a variable-length packet unit basis. A variable-length packet is divided into a group of cells in an ingress interface, and the cells are stored in VOQs divided in correspondence with destination output ports of a switch. For each of the VOQs, a corresponding first-cell storing register is provided. When a packet arrives at the head of the VOQ, the first cell indicating an output path of the packet is transferred to a first-cell storing register. Each ingress interface selects one of first cells of packets which can be output and transmits the selected one to the switch. The switch performs a scheduling process so as to select one first cell per output port. The ingress interface to which output permission is given by the scheduling process is connected to a desired output port, and continuously outputs the first cell and the subsequent cells stored in the VOQs to the output port on a packet unit basis.

Packet communication apparatus and controlling method thereof

Growing community of inventors

Isehara, Japan

Hirofumi Masukawa