A reliability assessment method for software products in operational phase—proposal of an accelerated life testing model

Abstract

To assess the reliability of software products, the differences between the testing phase and the operational phase must be clearly distinguished. In contrast to the former that makes assessments based only on the statistical properties of the fault detection mechanism observed in the testing process, the latter must be executed by predicting the differences between the environment in the testing phase (effort, test method, and so on) and the software operational environment such as the frequency of use. Previously, many reliability assessment methods for software products in the operational phase have been proposed. However, none have adequately modeled the software operational environments without conflicts. The general methodologies in this field have still not been established. In this paper, we propose a dynamic model to represent the phenomenon of software reliability growth in the operational phase by applying the concept of accelerated life testing of hardware. In addition, we investigate the effectiveness of our model by using both the fault detection time data obtained in the actual software testing process and the error occurrence time data observed in the operational phase. © 2001 Scripta Technica, Electron Comm Jpn Pt 3, 84(8): 25–33, 2001