Track 1 Session 9

8:00 to 9:00 a.m. Friday March 30, 2012

Estimating System Reliability in Combined Hardware and Software Projects

This presentation shows how to use the Weibull++ software with combined hardware and software projects. There are differences between the domains of hardware reliability and software reliability. Software failures are considered to be mostly due to human error, while hardware failures are usually considered to be the result of physical wearout or deterioration. The definition of software reliability is "the probability of failure-free operation of a computer program for a specified time in a specified environment." Well-proven hardware reliability concepts and terms — such as time to failure (TTF), mean time to failure (MTTF) and mean time between failures (MTBF) — are used in the domain of software reliability, but should be implemented very carefully. When we discuss a combined hardware and software project, the main question is how to describe the overall system reliability. A practical approach is to create a common system reliability as a function of both the hardware and software. The system reliability is anchored in the time domain, so we can use all the modeling techniques included in Weibull++.

Key Words: Life Data Analysis, TTF, MTBF, Software Testing, Estimation, Correlation, Weibull

Krzysztof Senczyna

Tieto Czech s.r.o.