Activity Network Diagram

The Activity Network Diagram was called the arrow diagram in the original N7 tools. Brassard renamed it to include other formats for modeling network activity. This tool is essentially a combination of Program Evaluation and Review Technique (PERT) and Critical Path Method (CPM), which were developed for operations research. PERT and CPM constitute important areas in project management. You can refer to a number of excellent texts on project management that cover this subject (see, for example, Kerzner).^[19] An activity network diagram also includes other network diagrams, such as node diagram, activity on node diagram (AON), and precedence diagram (PDM). This tool is used to plan the most appropriate schedule for a complex task when the task is a familiar one.^[20]

This chapter has introduced some very useful tools that deal with qualitative and verbal data. They are particularly valuable in planning, design, and development phases that have a profound effect on overall software quality. As we have stated, not all the tools are equally effective or even applicable in the contemporary software development environment. For example, prioritization matrices have been rendered redundant in light of AHP and accompanying software such as Expert Choice (see Chapter 8). Similarly, many users may prefer PERT and CPM rather than an activity network diagram. Effective use of appropriate tools can be powerful indeed. Affinity, tree, and matrix diagrams are relatively simple and remain popular as powerful quality tools.