Verification and validation

Abstract

Verification and validation are terms that are sometimes used interchangeably. In Ghezzi et al. [1991], verification is used to describe “all activities that are undertaken to ascertain that the software meets its objectives,” and validation is not used at all. In Rushby [1993], specification validation is a two-component process of seeking assurance that a specification means something (i.e., is consistent), and that it means what is intended. We use verification to describe the process of demonstrating that a description of a software system guarantees particular properties. General properties may be derived from the form of the description (e.g., that functions are total, axioms are consistent, or variables are initialized before they are referenced), and specific properties may be derived from the problem domain. The latter case involves the comparison of two objects, a detailed description of a software system, and a more abstract description of its intended properties.