Abstract
An information system (IS) is a system that communicates, transforms, and preserves information for human users. An information system comprises one or more software applications and databases, and their relationships to their human users, operators, and maintainers. A modern enterprise has many information systems that can be related in various ways. For example, information systems can be related by exchange because they exchange data through message passing or shared databases, or because they exchange functions through remote procedure calls or Web services. Information systems can also be related by overlap because they maintain the same data or provide the same functions. Information systems can be related in many other ways too, either directly, such as when one IS controls another, or indirectly, for example, because several ISs depend on the same run-time platforms or because they compete for their users’ attention or for computer resources. In addition to being related to one another, information systems can be related to the surrounding organization in many ways. For example, organization units such as departments, individuals, or roles may be the owners, users, operators, or maintainers of ISs; organizational goals and strategies can be realized by ISs; organizational processes can be supported or automated by ISs; and so on. The information systems (IS) architecture of an enterprise comprises its information systems, the relationships between those information systems, and their relationships to the surrounding organization. In addition to single enterprises, alliances of enterprises and parts of enterprises, such as divisions and departments, can have IS-architectures too. The above definition implies that every enterprise has an ISarchitecture, even if that architecture is not explicitly talked about, described, or managed: ‘IS-architecture’ is a way to look at organizations and their information systems.1 IS-architecture alignment is the process of selecting an IS-architecture vision towards which the architecture should be incrementally but systematically evolved. This article will present a model-supported framework for aligning an IS-architecture with its surrounding organization (Opdahl, 2003a). The framework shows how an enterprise’s current IS-architecture can be represented in an enterprise model, from which candidate architecture visions can then be generated, before one of them is selected as the enterprise’s IS-architecture vision.
TopIntroduction
An information system (IS) is a system that communicates, transforms, and preserves information for human users. An information system comprises one or more software applications and databases, and their relationships to their human users, operators, and maintainers.
A modern enterprise has many information systems that can be related in various ways. For example, information systems can be related by exchange because they exchange data through message passing or shared databases, or because they exchange functions through remote procedure calls or Web services. Information systems can also be related by overlap because they maintain the same data or provide the same functions. Information systems can be related in many other ways too, either directly, such as when one IS controls another, or indirectly, for example, because several ISs depend on the same run-time platforms or because they compete for their users’ attention or for computer resources. In addition to being related to one another, information systems can be related to the surrounding organization in many ways. For example, organization units such as departments, individuals, or roles may be the owners, users, operators, or maintainers of ISs; organizational goals and strategies can be realized by ISs; organizational processes can be supported or automated by ISs; and so on.
The information systems (IS) architecture of an enterprise comprises its information systems, the relationships between those information systems, and their relationships to the surrounding organization. In addition to single enterprises, alliances of enterprises and parts of enterprises, such as divisions and departments, can have IS-architectures too. The above definition implies that every enterprise has an IS-architecture, even if that architecture is not explicitly talked about, described, or managed: ‘IS-architecture’ is a way to look at organizations and their information systems.1
IS-architecture alignment is the process of selecting an IS-architecture vision towards which the architecture should be incrementally but systematically evolved. This article will present a model-supported framework for aligning an IS-architecture with its surrounding organization (Opdahl, 2003a). The framework shows how an enterprise’s current IS-architecture can be represented in an enterprise model, from which candidate architecture visions can then be generated, before one of them is selected as the enterprise’s IS-architecture vision.
TopBackground
Zachman (1978) defines ‘IS-architecture’ as “the sum total of all information-related flows, structures, functions, and so on, both manual and automated, which are in place and/or required to support the relationships between the entities that make up the business.” In the last few decades, several IS-architecture methods have been proposed in both industry and academia (Opdahl, 2003a).
A related term is information architecture (IA), used by some authors (e.g., Periasamy & Feeny, 1997) as a synonym to ‘IS-architecture’, although IA can also be used to emphasize the information sharing and information management aspects of IS-architecture. Another related term is enterprise architecture (EA) (McGovern et al., 2004), sometimes called enterprise information architecture (EIA) (Cook, 1996), which, according to Chorafas (2002), “is to align the implementation of technology to the company’s business strategy” and “to make technology serve innovation economics.” ‘EA’/’EIA’ is sometimes used synonymously with ‘IS-architecture’, but can also be used to emphasize organizational aspects such as process structure and organizational roles.
IS-architecture alignment can also be understood as an intermediate step (or level) between ICT strategy and detailed IS planning (Brancheau & Wetherbe, 1986).
TopIs-Architecture Alignment
A good IS-architecture should be strategically and operationally fit to the enterprise, simple and well structured, well managed, and clearly and explicitly described. These characteristics are explained as follows:
Key Terms in this Chapter
Information System (IS): A system that communicates, transforms, and preserves information for human users. An information system comprises one or more computerized data systems along with their human users, operators, and maintainers.
Enterprise Model: A diagrammatic representation of an enterprise or part of an enterprise. An enterprise usually focuses on certain aspects of the enterprise, such as its goals and strategies, its business processes, its organization structure, its information and knowledge, etc.
Information Systems Architecture, IS-Architecture: The set of information systems in an organization, the relationships between those information systems, and the relationships between the information systems and the rest of the organization.