A User's View of CARE III

A novel, powerful, computerized reliability predictor for highly reliable digital fault-tolerant systems has recently been developed and will soon be released. CARE III (Computer-Aided Reliability Estimation) was designed to model very large systems on the order of 106 Markovian equivalent states. Through the use of advanced stochastic modeling techniques, CARE III implements a mixed Markov model that enables it to drastically reduce the state size of hitherto computationally unreachable models that are of practical interest. This paper introduces the basic concepts of CARE III from a user's point of view. After describing the major attributes of the reliability evaluator, a discussion o the applicable class of fault-tolerant, digital-based computer architectures is presented. Following this discussion, the notions of failure, fault, and error are presented in the context of CARE III's fault/error-handling models. The paper concludes with a description of CARE III's user friendly interface and an example dialog portraying the assessment of a highly reliable fault-tolerant system. Also, some mention is made of the extensive testing and verification of the CARE III stochastic model and computer program.