Successful application of software reliability engineering for the NASA Space Shuttle

Summary form only given. The Space Shuttle Primary Avionics Software Subsystem (PASS) represents a successful integration of many of the computer industry's most advanced software engineering practices and approaches. Beginning in the late 1970's this software development and maintenance project has evolved one of the world's most mature software processes applying the principles of the highest levels of the Software Engineering Institute's Capability Maturity Model and ISO 9001 Standards. This software process, considered to be a "best practice" by many software industry organizations includes state-of-the-practice software reliability engineering (SRE) methodologies. Life-critical PASS produced by this process is recognized to be among the highest quality and highest reliability software in operation in the world. Using this application, we show how SRE can be applied to: interpret software reliability predictions, support verification and validation of the software, assess the risk of deploying the software, predict the reliability of the software, develop test strategies to bring the software into conformance with reliability specifications, and make reliability decisions regarding deployment of the software.