A New NHPP Reliability Model with Considerations of Hardware and Software Failures

Today almost everyone in the world is directly or indirectly affected by computer systems. Computers indeed are used in diverse areas for various applications including air traffic control, aircraft, automotive mechanical and safety control, and hospital health care, affecting many millions of people. Many software reliability growth models have been proposed. Most of the research in these areas has been limited to consideration of either the hardware system alone, or the software system alone. In these systems, the hardware and the software subsystem are not independent of each other, and consequently the system reliability is affected by interactions between them. In this paper, we present a unified software reliability model with considerations of two types of failures: hardware and software. The explicit mean value function of the proposed model is presented. We show that the proposed model appears to be the best descriptive by fitting several sets of data based on three criteria such as MSE, PRR and PP.