3.3 The General V- Model

The starting point for the development of software systems is the requirements definition, documenting the wishes and requirements of the customer and later users.

Requirements definition

Purpose, features, and quality requirements of the system under development must be documented in the requirements definition.

This document serves as a basis for all further development activities, in particular for the functional system design. Moreover, the requirements document forms the basis for the specification of the acceptance test. Requirements must be formulated accurately enough to be able to derive test cases from them.

During functional system design, the requirements are mapped onto functions and dialogues of the new system. The evolving documentation is required by the testers so that they can write the functional system test cases and test the user interfaces before the system undergoes customer acceptance testing.