Software Engineering Institute

Many organizations are planning to "emigrate" their legacy systems to distributed open system environments or a single product line of systems. Many of these efforts are often less than successful because they concentrate on a narrow set of software issues without fully considering a broader set of enterprise-wide management and technical issues. This report describes an enterprise framework that characterizes the global environment in which system evolution takes place and provides insight into the activities, processes, and work products that shape the disciplined evolution of legacy systems. Exemplary checklists are included to identify critical enterprise issues corresponding to each of the framework's elements. Preliminary results indicate that the enterprise model is a useful tool for probing and evaluating planned and ongoing system evolution initiatives. The model serves to draw out important global issues early in the planning cycle and provides insight for developing a synergistic set of management and technical practices to achieve a disciplined approach to system evolution.