A software reliability analysis considering testing environment and operational environment

Software reliability is the important aspect of any complex equipment today. Software reliability is evaluated based on the non-homogeneous Poisson process (NHPP) models. The testing and operation environments may be essentially different, thus the predicted reliability of the testing phase is different from that of the operational phase, namely, the testing reliability and the operational reliability is not similiar. On the basis of analyzing similarities and differences of the testing phase and the operational phase, using the operational reliability and the testing reliability, different forms of the comparison between the operational failure ratio and the predicted testing failure ratio are proposed, and the mathematical discussion and analysis are performed in detail. Finally, software optimal release is studied using software failure data, and the results show that two kinds of conclusions can be derived by applying this method, one conclusion is to continue test to meet the required reliability level of users, and another is that testing stops when the required operational reliability is met, thus the testing cost can be reduced.