Application of Independent Verification & Validation Analysis Techniques by Software Development Organizations

Abstract

Post loss analysis of e very major NASA missio n that failed over the last 7 years (Mars Polar Lander, Mars Climate Orbiter , and X-43 A) identified that Independent Verification & Validation (IV&V) was not applied to the missions software development effort and its absence was determine to be a factor in the loss of each mission. Software development organizations can benefit by applying IV&V techniques to each phase of the life cycle (requirements, design, code, test , and operations) when IV&V is not a formal part of the development effort. I. Introduct ion fter the 1 st X -43 A h ypersonic research aircraft was destroyed and both the Mars Polar Lander and the Mars Cl imate O rbiter missions failed , major independent review s were conducted to determine how and why each mission was lost and what could be done to mitigate the reason for the failures. This loss mitigation data would be applied to future missions. For all 3 missions two major t hreads emerged from the data: little or no systems engineering was applied and Independent Verification and Validation of flight and ground software, requirements, de sign and interfaces was not done . By not applying IV&V an opportunity to identify and resolve the primary reason for each failure was missed. Development organizati ons (aerospace contractors, Do D and c ommerci al) that apply IV&V techniques can expect better so ftware and system performance, h igher confidence in software reliability and a better chanc e for meeting program acceptance criteria. From a management perspective you can expect better visibility into de velopment, better decision criteria, reduced maintenance cost and reduced frequency of operation al changes to the code. Simply put the application of IV&V techniques revolve around two key goals :  making sure the right system is built  making sure the rig ht system is built the right way II. Application of IV&V Techniques IV&V is a system engineering process employing rigorous methodologies for evaluating the correctness and quality of the software product throughout the software life cycle. IV&V techniqu es should always be adapted to the unique characteristics of a program. When applying IV&V techniques, the development organization shou ld use a systems perspective, r eviewing the needs, systems use, interfaces and limitations of the software and developm ent team. When preparing to use IV&V techniques the development organization should start by addressing the following self -assessment criteria:  Determine the consequences of failure  Determine the likelihood of failure