Deriving complexity information from a formal communication protocol specification

Abstract

Communication software systems have become very large and complex. Recognizing the complexity of such software systems is a key element in their development activities. Software metrics are useful quantitative indicators for assessing and predicting software quality attributes, like complexity. However, most of existing metrics are extracted from source programs at the implementation phase of the software life cycle. They cannot provide early feedback during the specification phase; and subsequently it is difficult and expensive to make changes to the system, if so indicated by the metrics. It is therefore important to be able to measure system complexity at the specification phase. However, most software specifications are written in natural languages from which metrics information is very hard to extract. In this paper, we describe how complexity information can be derived from a formal communication protocol specification written in Estelle so that it is possible to predict the complexity of its implementation and subsequently its development can be better managed. © 1998 John Wiley & Sons, Ltd.