Autonomous decentralized system test technique

An online system test technique that does not interrupt system operation is proposed. It is based on an autonomous decentralized concept, in which each subsystem has autonomy to control itself and coordinate with the other subsystems. In the autonomous decentralized system architecture, each software module is connected only to the data field (DF), where the data are circulating, and selects whether or not to receive the data on the basis only of the content code of each datum. This means that there exists only one interface between software modules, which is the content code message interface. In this system, both real current data and test data can be circulated in the DF. Hence, a software module can autonomously judge whether to run or test itself on the basis of the received data, while the other software modules are operating. Each module can diagnose the other modules according to their test result data in the DF. The effectiveness of this system test mechanism is shown by applications to real-time control systems