Information Systems and Web Information Systems : a Methodological Perspective

The Development of Information Systems (ISD) is a complex activity that requires methodological support. Current ISD methods are predominantly following an object driven paradigm that allows us to capture the static as well as the dynamic dimensions of real world objects into information objects. However, Web Information Systems have facets such as information presentation, user profile, navigation structure etc. which pose new challenges to ISD methods. The keynote talk will provide an overview of current ISD methods and discuss the new challenges raised by the development of Web Information Systems. This paper is a brief overview of the key points developed in the talk. INFORMATION SYSTEM DEVELOPMENT In this section we briefly introduce the two-phase organisation of the process for developing information systems namely, Requirements Engineering as a prerequisite for System Engineering. We then, use the [Olle88] framework for classifying IS conceptual models that traditionally support the requirements engineering phase and comment their characteristics. We discuss the limitations of conceptual models as supports for ensuring the match of system functions to organisational requirements and then, introduce more recent requirements engineering models. Finally we comment the evolution of process models to support the modelling process. ISD organisation Traditionally Information System Development (ISD) has made the assumption that an information system captures some excerpt of world history and hence has concentrated on modelling information about the Universe of Discourse [Olle88]. Thus the IS development can be organised in two phases as shown in Figure 1. The first phase where conceptual modelling is carried out aims at abstracting the specification of the required information system i.e. the conceptual schema, from an analysis of the relevant aspects of the Universe of Discourse about which the user community needs information [Dubois89]. The succeeding phase, that of system engineering, uses the conceptual schema to design and implement a working system which is verified against the conceptual schema. ha l-0 07 07 55 0, v er si on 1 16 J un 2 01 2 Author manuscript, published in "Information Technology and Communication at the Dawn of the New Millennium, Thailand (2000)"