摘要 |
A standby system calculator communicates with a currently-used system calculator for retaining data about a service, providing the service by using the data, and updating the data along with provision of the service. The standby system calculator includes a retainer that retains a copy of the data and a provider that provides the service by using the copy of the data while restricting an updating operation for updating the copy of the data in the retainer when a predetermined signal that indicates that the currently-used system calculator is operating and that has been transmitted from the currently-used system calculator to the standby system calculator, cannot be received for a predetermined period of time. |