Developing a secure system is not enough; the system must be operated and maintained in line with rapidly changing technology. In addition, even a highly reliable system can fail, and it cannot be reliable if it does not restore itself immediately after a failure. Our aim is to prevent failure before it happens. With our regular system check we can detect potential problems in advance and prevent failures. If a failure still occurs, we devote every effort to the earliest possible recovery and briefest minimum impact on operations.