Hitachi, Ltd.

Other

Hitachi Microcomputer System, Ltd.

Norihide Noyama

Shinya Ichinohe

Tokuhiro Niwa

Masao Nakamura

Shigeki Morimoto

Takunori Yoneno

A network system includes a plurality of networks, a first internetwork apparatus having a plurality of first ports each connected to the plurality of networks, a second internetwork apparatus having a plurality of second ports each connected to the plurality of networks, and a data transmission path connected to the first and second internetwork apparatuses to transmit data mutually between the first and second internetwork apparatuses. In the normal state, each of the plurality of first ports is caused to be able to transmit and receive data to and from one of the plurality of networks and the plurality of second ports are caused not to be able to receive data from the plurality of networks and to be able to transmit data to the plurality of networks. Whether a failure occurs in any of one of the plurality of first ports and a route between one of the plurality of first ports and one of the plurality of networks connected thereto is detected and the one of the plurality of first ports is caused not to be able to transmit and receive data to and from the one of the plurality of networks in response to detection of occurrence of failure. One of the plurality of second ports connected to the one of the plurality of first ports through the one of said plurality of networks is caused to be able to transmit and receive data to and from the one of the plurality of networks in response to detection of occurrent of failure.

Network system having function of changing route upon failure

A network system has a plurality of networks. A first internetwork apparatus has a plurality of first ports each connected to the plurality of networks and a second internetwork apparatus has a plurality of second ports each connected to the plurality of networks. A data transmission path is connected to the first and second internetwork apparatuses to transmit data therebetween. In the normal state, each of the plurality of first ports is able to transmit and receive data to and from one of the plurality of networks while the plurality of second ports are able to transmit, but not receive data from the plurality of networks. A failure occurring in one of the plurality of first ports and a route therefrom to one of the plurality of networks is detected.

In an internetwork apparatus for interconnecting a plurality of networks having a route calculating module for calculating routes and a management module for managing a whole operation of the internetwork apparatus, the management module substitutes for route calculation in place of the route calculating module, when a fault occurs in the route calculating module, and packets are repeated in accordance with route calculation results made by the management module.

Growing community of inventors

Hadano, Japan

Norihide Noyama