Architectural domain

An architecture domain in enterprise architecture is a broad view of an enterprise or system. It is a partial representation of a whole system that addresses several concerns of several stakeholders. It is a description that hides other views or facets of the system described.

Since Stephen Spewak's book called enterprise architecture planning (EAP) in 1993, and perhaps before then, it has been normal to recognise four types of architecture domain. The British Computer Society's "Reference Model for Enterprise and Solution Architecture" also follows this subdivision but additionally mentions the (single) application architecture level just below the applications architecture as well as the domains of information architecture, information systems architecture, or security architecture (a cross-cutting concern):

Note that the applications architecture is about the application portfolio, not the internal architecture of a single application - which is often called the application architecture.

Many EA frameworks combine data and application domains into a single layer, sitting below the business (usually a human activity system) and above the technology (the platform IT infrastructure). There are many variations on this theme.

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