DoD legacy systems

Abstract

As with most large organizations, the Department of Defense has both strategic and economic needs to capitalize on and to consolidate existing information systems. This paper reports on a framework currently being used to reverse engineer selected legacy information systems in DoD's heterogeneous environment. This generic approach was developed to recover organizational business rules, business domain information, system functional requirements, functional dependencies, and system data architectures, largely in the form of normalized logical data models. We are applying the approach as a series of pilot studies on systems ranging from those using home grown languages and database management systems developed during the late 1960's to those using high order languages and commercial network database management systems. These pilot studies are being used to validate and refine the framework with real-life systems; to develop a baseline approach for reverse engineering DoD legacy information systems; and to scope and estimate future system re-engineering costs. Furthermore, the results of these projects will help to determine the economic viability of re-engineering, reverse, and forward engineering efforts for these legacy systems.