Abstract
It is difficult to maintain information systems safely and effectively because information systems become complicated according to the spread of Internet and cloud infrastructures. The previous definitions of operation and maintenance activities of the information systems are inadequate to stably offer the functions of the information systems to users. We consider operation and maintenance activities of the information systems from the viewpoint of IT service for users instead of the viewpoint of maintenance activities that mainly repair and enhance. We first investigate the details of the previously defined operation and maintenance activities. Then we compare these activities with ones that were defined in the IT service management. Finally, we discuss definitions of operation and maintenance activities of the information systems.
