Adding Value to the Software Development Process: A Study in Independent Verification and Validation

Independent Verification and Validation (IV&V) is best viewed as an overlay process supporting a software development effort. While the touted benefits of a properly managed IV&V activity are many, they specifically emphasize: (a) early fault detection, (b) reduced time to remove faults, and (c) a more robust end-product. This paper outlines a study funded by NASA-Langley Research Center to examine an existing IV&V methodology, and to confirm (or refute) the touted beneficial claims. In the study two distinct development groups are established, with only one having an IV&V contingent. Both groups are tasked to produce a software product using the same set of requirements. Within each phase of the development effort, fault detection and fault removal data are recorded. An analysis of that data reveals that the group having the IV&V contingent: (a) detected errors earlier in the software development process, and (b) on the average, required significantly less time to remove those faults. Moreover, a test for operational correctness further reveals that the system developed by the group having the IV&V component was substantially more robust than the one produced by the other development group. A statistical analysis of our results is also provided to establish significance.