Strategies for the Conceptual Design of Federated Information Systems

We analyse two basic strategies for the development of tightly coupled, federated information systems: top-down and bottom-up. Both approaches are compared relative to the specific requirements of information integration in evolving environments, such as the intention of treating different kinds of heterogeneity, preserving source autonomy and enabling change management while ensuring consistency. We describe in detail how the intrinsic properties of such strategies affect their ability to cope with these requirements. Based on the results of this study and on extensive experiences, we propose a combined strategy based on the intensive use of object-oriented modelling concepts. We show that this approach is well-suited to fulfil our vision of a consistent evolution within the paradigm of continuous engineering of federated information systems.