An extended domain-based model of software reliability

A definition of software reliability is proposed in which reliability is treated as a generalization of the probability of correctness of the software in question. A tolerance function is introduced as a method of characterizing an acceptable level of correctness. This in turn is used, together with the probability function defining the operational input distribution, as a parameter of the definition of reliability. It is shown that the definition can be used to provide many natural models of reliability by varying the tolerance function and that it may be reasonably approximated using well-chosen test sets. It is also shown that there is an inherent limitation to the measurement of reliability using finite test sets.<>