Enhancing Requirements and Change Management through Process Modelling and Measurement

Luigi Lavazza and Giuseppe Valetto

CEFRIEL and Politecnico di Milano

Abstract

Effective management of requirements is of vital importance for any software development effort. This activity spans from software procurement to project management, to the technical development activities.

We present a methodology that aims at improving the effectiveness of requirements management in software development and maintenance. In particular, we address quantitative assessment of the impact of requirements changes, and quantitative estimation of costs of the development activities that must be carried out to accomplish those changes.

Our approach is based on enhanced traceability and process measurement. Traceability relations are derived from an integrated view of the process and product models adopted within the software development organization. Hence, traceability spans over all the software life cycle and its products. Moreover, through proper measurement, the elements in the process and product models are quantitatively characterised, thus achieving a sound basis for different kinds of sophisticated analysis concerning the impact of requirements changes, their cost over the development process, and the sensitivity of the product to changes.

The methodology presented here is the basis of the ESPRIT project SACHER. In this project a tool supporting the proposed approach was developed, and both the methodology and the tool were used in different case studies, in order to assess their ability to handle the complexities inherent in the technical, managerial and contractual dimensions of requirements and change management.

Keywords: requirements management, change management, traceability, software process modelling, software measurement, cost estimation.