Understanding and managing the relationship between requirement changes and product constraints in component-based software projects

The recent surge of interest in component based software engineering (CBSE) represents a strong re emergence of systems integration within the software industry. This approach comprises the acquisition adaptation, and integration of reusable software components, often are purchased off the shelf to enable rapid deployment of complex systems with minimum development effort and resource cost. While the number of CBSE based projects continues to increase, small percentage can be claimed success. The paper asserts that the existence of a cyclical dependency between requirement change and reusable software component selection creates fundamental project management problems in component based software development. This is due to: (1) the high cost in effort and time required to re-evaluate, reselect, and reintegrate reusable software components to support new changes in the overall system requirements; and (2) the high cost in effort and time required to re-evaluate, renegotiate, and rewrite the system requirements to reflect the constraints of the underlying software components selected. We use our experience in building component based distributed network management systems to illustrate the problems with cyclical requirement component dependency in CBSE. We also present a set of effective risk mitigation strategies that have been adopted to minimize these problems in ongoing CBSE projects