System complexity as an aid to quality assurance

Designing a good software system is a very complex task. In order to produce a good software product, several measures need to be taken into account. System complexity generally affects attributes such as software reliability, maintainability, and testability of software systems which are considered of immense importance in designing a better software product. For achieving these software qualities, its system complexity must be controlled by modularizing the system into various modules of appropriate complexities. The paper reports the system complexity which is comprised of internal and external complexities. External complexity, a result of software decomposition, which is mainly contributed by the coupling or interaction among modules, is derived by taking into account the proposed reasonable modular coupling complexities.