Challenge of validation in requirements engineering

- Framing the issue of validation in Requirements Engineering.
- Classification and taxonomy of existing techniques in requirements validation.
- A validation techniques is intended for a particular area.
- The combination of validation techniques is essential.
- Several iterations are necessary because of the multidisciplinary projects.

This paper will review the evolution of validation techniques and their current status in Requirements Engineering (RE). We start by answering the following questions: What validate? Why the benefits of having the requirements validation activities during the RE process? Who are the stakeholders involved in the requirements validation process? Where applied the validation in the RE process? and How the techniques and the approaches of requirements validation?