IV&V Case: Empirical Study of Software Independent Verification and Validation Based on Safety Case

We describe a framework for constructing an IV&V case, which is an expanded safety case, in order to apply Independent Verification and Validation (IV&V). The objectives of IV&V at the Japan Aerospace Exploration Agency (JAXA) are to reduce and explain the risks of products. Although a safety case is a useful framework to explain the risks to customers, virtually all past studies on safety cases focused on safety standards that provide risk assurance in the software development process. Therefore, we provide a framework to construct IV&V cases based on the risks of a software product. In order to evaluate our framework, we compared the results of past IV&V and current IV&V. Our comparison found that current IV&V pointed out four times more valid issues than past IV&V. Moreover, the time costs of current IV&V were about half the costs of past IV&V.