Enterprise Information Systems Management An Engineering Perspective Focusing on the Aspects of Time and Modifiability

Evolution of information systems (ISs) is a multi-facetted issue that over time has proved arduous to manage. On the enterprise level of ISs, an organization's total portfolio of interconnected information systems is considered as one system – an enterprise information system (EIS), consisting of course-grained and heterogeneous components that in themselves may constitute complex ISs. In EISs, considerations concerning legacy systems and commercial-off-the-shelf software (COTS) are pervasive. This doctoral thesis addresses management of EISs in primarily small and medium-sized electric utilities that are active on the reformed Swedish electricity market. The enabling reasons for the choice of electric utilities as unit of analysis are the implications of the recent electricity market reformation, utilities' broad range of interconnected ISs, and small and medium-sized enterprises' sparse resources for strategic management. This work applies an engineering perspective on EISs management by investigating how description techniques and analysis methods from software architecture may be employed as decision support during planning and implementation of system evolution activities. An enabling motivation for the selection of software architecture as reference discipline for this work is its recent achievements in expressing and analyzing complex software systems consisting of coarse-grained software packages, on the basis of quality attributes. A special emphasis is hereby placed on modifiability and the implication of time. Presented findings imply that the concepts for architectural description, e.g. quality attributes, architectural taxonomy, and architectural integration styles, combined with scenario-based architectural analysis, may successfully contribute to enhance the comprehensiveness of the complex problem domain provided by EIS evolution. The chosen approach promotes structured analysis, as well as stakeholder communication and awareness. This work also suggests adaptations of the investigated architectural concepts to increase their applicability on the enterprise level of ISs in small and medium-sized enterprises.