An Approach to Modelling Legacy Enterprise Systems

The reclamation and redevelopment of software "brownfield sites" requires a multi-layered understanding of the domain in which the enterprise system lives. A further dimension is added to the interconnectivity of the domain knowledge when the evolution of the system requires the migration of existing services to a web-based system and the creation of new value-added services. Where the enterprise systems are both internal to the organisations and "joined up" into wider interorganisational networks, there are further challenges to developers. The Institutionally Secure Integrated Data Environment (INSIDE) project is addressing the problems and issues surrounding the development and delivery of web based services for joined up systems within Higher Education (HE) Institutions. The project is working with a variety of legacy systems including the existing information systems, e.g. student record systems and virtual learning environments, at two universities. Initially a common business process, the registration of new undergraduate students, was analysed and modelled at both sites. The analysis and modelling of what was believed to be a simple and common process has provided the first attempt at the reclamation of knowledge within a brownfield site: the domain vocabulary; the existing business processes; associated information bases and legacy systems. Through trial and refinement, the project has developed an approach to analysis and modelling using some of the UML notations preceded by the development of a common abstracted vocabulary in the form of a Thesaurus. Having worked through the process of developing an initial and formal domain model of the registration process, it became clear that our experiences could be abstracted in the form of a meta-process that would provide guidance to other analysts and designers working in the area of brownfield site evolution and using UML. In this paper we define the meta-process that has emerged as a way to support incremental implementation of value-added services. This definition includes identification of the relationships that exist amongst the generated work products in context with the metaprocess.