System reliability using binomial failure rate

A method is presented for calculating the reliability of a computer system subject to common-cause failures described by the binomial failure rate model. This model takes into account three types of shocks; shocks causing individual components to fail and common-cause shocks of both a nonfatal and a fatal type. The probability that all the components of each subsystem are good is computed. The system reliability is then obtained by simple substitution of these probabilities for the respective counterparts of the system reliability computed under the assumption of statistically independent components. An example demonstrating how to use the method is given