School of Computing Science

PhD Theses

The Effect of Diverse Development Goals on Computer-Based System Dependability (2006)

The full text of this thesis is available from the Newcastle University Library website: https://theses.ncl.ac.uk/dspace/handle/10443/1992

Lawrie, A.T., School of Computing Science, University of Newcastle upon Tyne

Society's increasing dependence upon software control and information processing provision has demanded comparable increases in software dependability. While the existing software dependability approach has resulted in significant improvements, its focus is heavily aimed towards achieving software dependability via redundant fault-tolerant mechanisms built into the software artefact to provide error-control in the presence of activated faults. Less emphasis appears to have been placed upon how software dependability can also be promoted through a fault-avoidance approach in the software creation process by incorporating human redundancy and diversity. In this thesis, a process intervention which can potentially improve fault-avoidance is considered. This involves the setting of diverse development goals within important generic computer-based system contexts in order to increase detection of potentially harmful assumptions which can result in subtle systemic conflicts that can undermine the dependability of the resultant artefact during the early development phases of requirements, specification and design. A search theoretic simulation model is progressed and developed to capture some of the important dynamics involved. The eventual outputs of the simulation model indicate that increased fault coverage and sensitivity can be obtained through the setting of diverse development goals during the early phases of software development.