Fujitsu Corporation

Junichi Shimada

Satoshi Kumano

Koichi Saiki

Youichi Konuma

Akira Miyasaka

A transmission device is connected to a layerswitch through a transmission path at one side, and to a relay transmission path at the other side. The transmission path includes a transmission path of a active system and a transmission path of a stand-by system. When failure occurs in the transmission path of the active system, the transmission device forcibly shuts down the transmission path of the active system upon detection of link down, to stop packet transmission, and causes the layerswitch to perform MAC address flush. The transmission device then switches the transmission path of the stand-by system to the active system, and transmits packets through the transmission path that has become the active system as a result of switching. The layerswitch performs MAC address learning to set a port, thereby maintaining communication even after occurrence of the failure.

Transmission device and redundant configuration between transmission device and layer 2 switch

A communication controlling apparatus includes a receiving side communication protocol identifying means for determining a candidate communication protocol for a second apparatus. If an acknowledgment response is received from the second apparatus, a communication protocol is determined to be a candidate communication protocol for the second apparatus and, if no acknowledgment response is received, operations to convert a first signal into another signal conforming to another communication protocol supposed to be adopted by the second apparatus and to transmit the other signal to the second apparatus are repeated till an acknowledgment response to the other signal is received from the second apparatus. The apparatus also has a communication protocol converting means converting the first signal into another signal conforming to another communication protocol supposed to be adopted by the second apparatus, and a communication protocol conversion controlling means controlling the communication protocol converting means. If a first communication protocol is different from a protocol at the receiving side, a command is given to the communication protocol converting means to convert the first signal into another signal conforming to the communication protocol identified by the protocol identifying means at the receiving side.

Communication controlling apparatus and recording medium for recording communication controlling programs

In order to lighten the processing load on each monitoring device and enable each monitoring device to recognize the operating condition of a network as a whole, each monitoring device monitors operating conditions of transmission devices in a subnetwork allocated thereto and reports the operating conditions to the other monitoring devices periodically or when there is a change in the operating condition. Further, in order to enable of a change of the monitoring zone by the monitoring device due to a trouble or the like, the monitoring device holds supervisory screen image data which corresponds to various monitoring zone, and when a predetermined monitoring zone is designated, the monitoring device displays a supervisory screen image on the basis of the supervisory screen image data which corresponds to the designated monitoring zone and also displays the operating conditions of the transmission devices in the monitoring zone.

Load distribution system for monitoring device

A network monitoring system having at least one monitoring device and a plurality of transmission devices connected to a network includes a first data storage unit, provided in the at least one monitoring device, which stores first status information of all of the transmission devices, and an information attaching unit, provided in the at least one monitoring device, which attaches abridged status information of at least one of the transmission devices to a polling command and sends the polling command to the at least one of the transmission devices, wherein the abridged status information is generated to reflect the first status information. The network monitoring system further includes a second data storage unit, provided in each of the transmission devices, which stores second status information of a corresponding one of the transmission devices, and a comparison unit, provided in each of the transmission devices, which checks if there is a mismatch between the abridged status information of a corresponding one of the transmission devices and the second status information.

Growing community of inventors

Kawasaki, Japan

Junichi Shimada