MARKOVIAN MODELING FOR SOFTWARE AVAILABILITY ANALYSIS UNDER INTERMITTENT USE
Koichi Tokuno, Shigeru Yamada · International Journal of Reliability Quality and Safety Engineering · 2001
We discuss the software availability modeling when the system is used intermittently. From the viewpoint of users, occurrence of a system failure is recognized when the event that either a software failure occurs when the system is in use or a usage demand occurs when the system is under restoration arises. In this pape, a couple of new measures for software availability assessment are derived; these are called the disappointment probabilities in use and under restoration, respectively. It is supposed that the usage demand of the system occurs randomly and that the user's demand duration is also random. The time-dependent behavior of the system alternating between up and down states is described by a Markov process. Then the software reliability growth process, the upward tendency in difficulty of debugging, and the imperfect debugging environment are also considered.