Software Quality Management CIS 376 Bruce R Maxim UM Dearborn Software Quality Management Concerned with ensuring the required level of quality is achieved in a software product Involves the definition of appropriate quality standards and the definition of procedures to ensure that these standards are followed Works best when a quality culture is created where quality if seen as everyone s responsibility Quality Definition Quality means that a product satisfies the demands of its specifications It also means achieving a high level of customer satisfaction with the product In software systems this is difficult customer quality requirements e g efficiency or reliability often conflict with developer quality requirements e g maintainability or reusability software specifications are often incomplete inconsistent or ambiguous Quality Management Activities Quality assurance establishing organizational quality standards and procedures Quality planning selecting and modifying applicable quality standards and procedures for a particular project Quality control ensuring quality standards and procedures are followed by development team Note Quality management should be separated from project management to ensure independence ISO 9000 International set of standards for quality management Quality standards and procedures must be documented in an organizational quality manual An external body is often used to certify that the quality manual conforms to ISO 9000 standards Many customers are demanding that suppliers are ISO 9000 certified ISO 9000 and quality management ISO 9000 quality models instantiated as Organization quality manual documents is used to develop Project 1 quality plan Project 2 quality plan instantiated as Project 3 quality plan Supports Organiza tion quality process Project quality mana gement Quality Standards Key to effective quality management Product standards define the characteristics exhibited by all components e g programming style issues Process standards describe how a software process is to be implemented Should encapsulate best practices this helps avoid repeating past mistakes Provide continuity by giving new team members a means to understand the organizational priorities Process and Product Standards Product Standards Design review form Document naming standards Function prototype format Programming style standards Project plan format Change request form Process Standards Design review guidelines Document submission procedures Version release process Project plan approval procedure Change control process Test data recording procedures Problems with Standards Sometimes viewed by software engineers as neither up to date or relevant to the current project Can involve lots of bureaucratic form completion and submission Often not supported directly by software tools and this can mean lots of manual work to maintain standards Quality Standards Development Should involve practitioners in their development Engineers must understand the rationale behind each standard Standards must be reviewed and revised regularly to avoid obsolescence and credibility problems with practitioners Detailed standards need tool support to eliminate the too much clerical work excuse for not following the standards Documentation Standards Documentation process standards describe how documents are to be developed validated and maintained Document standards concerned with document content structure and appearance Document interchange standards specify how documents are to be stored and shared between different documentation systems Documentation process Create initial draft Stage 1 Creation Proofread text Stage 2 Polishing Layout text Stage 3 Pr oduction Incorporate review comments Review draft Re draft document Approved document Produce final draft Check final dr aft Approved document Review layout Produce print masters Print copies Document Standards Document identification standards how documents are labeled Document structure standards organization of project documents Document presentation standards fonts styles logos etc Document update standards change control and version definition Document Interchange Standards Allow documents produced on different computers using different tools to be exchanged among team members The lifetime of many word processing systems is often less than the lifetime of the software being documented document archival can be tricky Document interchange standards like XML are beginning to emerge as partial solutions to these problems Process Based Quality Product quality is influenced by the quality of its production process This relationship is easy the see in the manufacture of goods it is more complex for software production because the application of individual skills and experience is particularly important in software development external factors e g application novelty or need to accelerate schedule are more likely to impair quality Process Based Quality Activities Define process De velop product Improve process Assess product quality No Quality OK Yes Standar dize process Process Quality Overview Determine the process standards to be used e g review procedures configuration management etc Monitor the development process to ensure standards are being followed Report process findings to project manger and customerProcess based quality Quality Plan Identifies the most significant quality attributes appropriate for the product Defines the assessment process in detail for each quality attribute Indicates which organization standards should be applied and defines new standards as necessary Quality Plan Components Product introduction Product plans Process descriptions Quality goals Risks and risk management Software Quality Attributes Safety Security Reliability Resilience Robustness Understandability Testability Adaptability Modularity Complexity Portability Usability Accessibility Reusability Efficiency Learnability Quality Control Examines the software development process to ensure that all relevant procedures and standards are being followed Two basic approaches quality reviews software measurement and assessment Reviews Reviews are the principle means of validating both process and product quality Basic procedure is to have a group of people examine a process artifact to find potential problems Common software review types include defect inspection and removal product progress reviews product and process quality reviews product and standards Quality