Abstract According to ANSI/IEEE Std 1471-2000, architecture is defined as the "fundamental organization of a system, embodied in its components, their relationships to each other and the environment, and the principles governing its design and evolution" [8] . Enterprise architecture (EA) therefore is understood as (1) the fundamental organization of a government agency or a corporation, either as a whole, or together with partners, suppliers and / or customers ("extended enterprise"), or in part (e.g. a division, a department, etc.) as well as (2) the principles governing its design and evolution. [12] While an EA model is a representation of as-is or to-be architecture of an actual corporation or government agency, an EA framework provides [12] • one or more meta-model(s) for EA description, • one or more method(s) for EA design and evolution, • a common vocabulary for EA, and maybe even • reference models that can be used as templates or blueprints for EA design and evolution. The components of an EA framework should be applicable for a broad range of corporations and government agencies. Traditionally, architecture in the information systems context is focusing on IT related artifacts like IT platforms, software components and services, applications, IT processes, and maybe IT strategy in order to support more efficient IT operations, better return on IT investment, and faster, simpler and cheaper IT procurement. [12] In contrast to this approach which better should be designated information systems architecture (ISA), EA should also include business related artifacts like organizational goals, products and services, markets, business processes, performance indicators, etc. [1] Only when 'purely' business related artifacts are covered by EA, important management activities like business continuity planning, change impact analysis, risk analysis and compliance can be supported. The above definition of architecture restricts included components to be 'fundamental'. Due to the broad range of relevant component types, EA may nevertheless comprise a huge number of such artifacts. As a consequence, most EA frameworks distinguish several architecture layers and architecture views in order to reduce the number of artifacts per model [16, 18] . When several architecture layers and architecture views are differentiated, design and evolution principles have to address consistency and integration issues.
A multilayer architecture in REF contains business, process, integration, software, and technology architecture layers.
Essential Layers, Artifacts, and Dependencies of Enterprise Architecture
2006 10th IEEE International Enterprise Distributed Object Computing Conference Workshops (EDOCW'06)
2006 10th IEEE International Enterprise Distributed Object Computing Conference Workshops (EDOCW'06)
Computer Science