use is often incorrectly attributed to John Zachman's 1987 paper, which did not use the term "Enterprise Architecture". The scope of the report by the NIST "enterprise architecture" panel may be directly compared to Zachman's current thinking presented in the 1987 article which is as follows: "With increasing size and complexity of the Implementations of Information systems it Is necessary to use some logical construct (or architecture) for defining and controlling the interfaces and the Integration of all of the components of the system. The discussion is limited to architecture and does not include a strategic planning methodology." In the 1989 NIST article, enterprise architecture is described as consisting of several levels. The top-level is "Business Unit Architecture". The document describes this as follows: "A Business Unit may portray either a total corporate entity or a corporate sub-unit. Architecture at this level establishes a framework for satisfying both internal information needs and the information and data needs to be imposed by external organizations. These external organizations include cooperating organizations, customers, and federal agencies. The information and data needs at this level impose requirements to be satisfied at lower levels of the architecture, with increasing attention to technical considerations." The 1989 NIST document continues: "The representation of the Business Unit architecture shows organizational units and their relationships, as well as specific standards, policies, and procedures that enable or constrain the accomplishment of the overall enterprise mission." By examination, the evidence shows that Zachman's concept was the creation of an individual information system, perhaps composed of subsystems, optimized for a business case. However, the NIST conception describes the management of all the information systems in a business unit which may be the whole enterprise. Zachman did not use the exact term "enterprise architecture" in a publication until several years later. See also Origins of enterprise architecture Enterprise architecture artifacts Enterprise architecture framework Architectural pattern (computer science) Architecture of Integrated Information Systems Architecture of Interoperable Information Systems John Zachman, promoter of enterprise architecture Enterprise Architecture Service Life Cycle - SOMF References External links Information science Systems engineering