Nec Corporation

Yohei Umezawa

Yasushi Toda

In a cluster system having two server apparatuses that operate as an in-use type or a standby type, a first server apparatus is provided with: a heartbeat transmission/reception part that transmits and receives heartbeat packets to and from a corresponding second server apparatus; and a corresponding node monitoring part that adjusts a timeout period for transitioning operation of the first server apparatus from a standby type to an in-use type, according to the reception state of the heartbeat packets.

Server apparatus, cluster system, cluster control method and program

In a communication system using a standby screen, a portable communication terminal accesses a communication server at a predetermined time interval, uses RSS to receive and store new messages in a cyber sub-community in which the portable communication terminal participates, and sequentially displays tag buttons on the standby screen to display new-message arrivals with message-issuing member names and titles displayed on the buttons.

Communication system, device and program for exchanging messages between members of cyber communities

In an optimum route calculation method of calculating an optimum route in a network which has a plurality of nodes and a plurality of transmission paths, and in which a cost is defined for each transmission path, an evaluation value is obtained on the basis of the maximum cost of each transmission path included in a determined route and a route to be evaluated and the number of hops from the determined route to the route to be evaluated. A route is determined on the basis of the evaluation value. A storage medium which stores the optimum route calculation program is also disclosed.

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Tokyo, Japan

Yohei Umezawa