Danish White Paper on Enterprise Architecture
Download: Whitepaper on it-architecture 1.6 MB
On June 13 2003 the Danish Ministry of Science, Technology and Innovation published a national white paper on enterprise architecture. The white paper has been prepared by a working group with representatives from the state, the counties and the municipalities, and was commissioned by the Coordinating Information Council.
The main recommendations are:
- The public sector – at agency level and at large – should take a more active responsibility for its own enterprise architecture.
- Government should create a joint enterprise architecture framework for the planning of government IT systems with a particular focus on securing interoperability.
- A pronounced effort to raise awareness, spread knowledge and develop competencies with regard to enterprise architecture, especially around joint government initiatives.
The joint enterprise architecture framework should have the following elements:
- Joint coordination, including the establishing of a National Enterprise Architecture Committee with reference to the Coordinating Information Council.
- Common methodologies in terms of processes, concepts and description standards for enterprise architecture.
- Common choices regarding standards and infrastructure, including usage of a common reference profile (e-GIF) and common architectural principles.
- Common tools, e.g., by using shared databases and libraries of contract models, process descriptions, data definitions, software components and infrastructure patterns.
An increased focus on enterprise architecture and a good amount of cross-governmental coordination efforts are essential for realising the visions about eGovernment.
As a common architectural principle, the whitepaper recommends government to adopt a service-oriented architecture model, in which IT-solutions are modularly designed services that have well-defined interfaces to each other and to legacy systems. In a service-oriented architecture model it is a basic principle to organise components in layers that offers and uses each others’ services.
Web services are a specific implementation of a service-oriented architecture. The concept services can be understood at several levels:
- Conceptually, service-oriented architecture represents a model of loosely-coupled applications working together by exposing services to each other
- Businesswise, services are expressing data- and function-services that one party can offer other parties to use, for example on businesslike terms.
- Technologically, service-orintered technology consists of a group of emerging standards that define protocolls and creates a loosely-coupled framework for programmed communication between different systems.
- Concretely, web services is a notion that describes a method which enables an application to be invoked by other applications by receiving and sending data in standardised XML.
The service-oriented architecture doesn’t in itself prescribe any particular technical standards, even though several vendors offers technical solutions. The standardisation process for web services standards takes places in various international organisations (W3C, OASIS, WS-I, …).
The white paper points out 5 core architectural principles:
The architectural process should embrace the core principles. The process is seen as a double-loop process. In one loop, the main architectural process, the enterprise visions are used to define business process architecture, then information architecture, and then the technical architecture. This process defines the concrete architectural principles which are used in the implementation process, the second loop. This process consists of portfolio planning, gap analysis, and implementation projects.