An architectural connectivity metric and its support for incremental re-architecting of large legacy systems

Architectural connectivity metrics are a means of supporting incremental re-architecting of large legacy systems. These metrics provide support by giving an indication of the degree of connectivity between or within architectural entities in the system. Ideally, a connectivity metric should provide useful information in as many situations as possible. However, the existing metrics of cohesion and coupling provide support only in a limited number of situations. In this paper, we present a new architectural connectivity metric, referred to as directed connectivity, together with an appropriate visualization. Directed connectivity is a measure of the relative number of connections from one architectural entity to another. The metric is applicable in a large number of situations, including ones where cohesion and coupling fall short. The metric is visualized by means of a tabular representation with browsing facilities. A description is given of initial experiences with directed connectivity and its visualization on a large industrial system