An empirical study on reliability modeling for diverse software systems

Reliability and fault correlation are two main concerns for design diversity, yet empirical data are limited in investigating these two. In previ-ous work, we conducted a software project with real-world application for investigation on soft-ware testing and fault tolerance for design diver-sity. Mutants were generated by injecting one sin-gle real fault recorded in the software development phase to the final versions. In this paper, we per-form more analysis and experiments on these mu-tants to evaluate and investigate the reliability fea-tures in diverse software systems. We apply our project data on two different reliability models and estimate the reliability bounds for evaluation pur-pose. We also parameterize fault correlations to predict the reliability of various combinations of versions, and compare three different fault-tolerant software architectures.