Independent Verification and Validation IVV Techniques for Object

Independent Verification and Validation (IV&V) Techniques for Object Oriented Software Systems Executive Level Briefing SAS meeting July 2004

Outline Problem Approach Importance/benefits Relevance to NASA Accomplishments Next steps COMPANY PROPRIETARY 2 APC 0342

Problem Statement NASA has considerable experience applying IV&V to traditional function-based software systems Emerging use of OO brings unique challenges and risks There is a need to develop IV&V techniques for addressing these risks COMPANY PROPRIETARY 3 APC 0342

Approach Risks identified – Management, technical, process Developed base set of IV&V Techniques – Use cases, class diagrams, state transition diagrams Applied & evaluated techniques on the use cases based on a NASA example – Data for BBN, A set of use cases processed using the proposed approach COMPANY PROPRIETARY 4 APC 0342

Importance / Benefits Improved analysis of UML artifacts – Framework for use cases, classes, state transition diagrams • Method for prioritization of UML artifacts • Analysis techniques for the artifacts (consistency, completeness, traceability) Better maturity estimate during SSR, PDR, CDR – At present maturity estimate is based on “expert opinion” – BBN will allow for the use statistical methods to measure the completeness level of inputs to the milestone reviews COMPANY PROPRIETARY 5 APC 0342

Relevance to NASA More NASA systems are using object oriented approach – JWST, HDS, …. NASA IV&V needs better techniques to support milestone reviews – Use of BBN – Improved process model COMPANY PROPRIETARY 6 APC 0342

Accomplishments Techniques for OO models – – Evaluated current & emerging OO IV&V techniques Identified Risks with OO development Investigated framework for OO IV&V Developing base set of IV&V techniques for Use cases, Class diagrams, State diagrams – ISSRE 2003 “IV&V of OO software systems” BBN based maturity estimate during SSR – ISSRE 2004 “A Probabilistic Framework to Support Independent Assessment of Use-Case Based Requirements Specifications” NASA project example analysis COMPANY PROPRIETARY 7 APC 0342

Next Steps Process model – Developing Use case IV&V process model • Use case IV&V workflow • Need to refine further the IV&V steps for use case analysis Improved BBN models – Basic BBN model is ready and submitted to a conference Extend the IV&V models to other phases – Near term-process model for the analysis of class diagram, state transition diagrams – Longer term- BBN models for the class diagram, state transition diagrams COMPANY PROPRIETARY 8 APC 0342