The Enterprise Architecture Framework (EA) frequently called the Zachman Framework, was introduced in 1987 by John Zachman and extended by Sowa in 1992 (Sowa and Zachman 1992). As it applies to enterprises, this framework is a logical structure for classifying and organizing the descriptive representations of enterprises that are significant to enterprise management as well as to the development of enterprise systems
What does the Zachman Framework look like?
The Zachman Framework appears as a matrix containing 30 cells, each cell focusing on one dimension or perspective of the enterprise.
Rows often represent the levels of abstraction involved in system development processes, while columns represent the different perspectives also involved in the cycle. These rows, however, are really different dimensions, each one being candidate to decomposition and realization layers and handling various levels of abstraction.
Zachman and his followers established a set of rules for interpreting and using the original framework (see Bruce, 1992). These may be summarized as follows.
Rule 1: The columns have no ordering. None is more important than the other but focusing on one may have significant practical implications.
Rule 2: Each column represents a unique model.
Rule 3: Each column is unique although they are all interconnected.
Rule 4: Each row represents a unique perspective.
Rule 5: Each cell is unique (no item should appear in more than one cell).
Rule 6: Each row is a complete model, from the row's perspective.
Rule 7: The logic is recursive and generic.
Advanteges of Zachman Framework
There are four reasons why you do Architecture: "Alignment", "Integration", "Change," and "Reduced Time-to-Market".”
- Do you care that the systems I/S is producing actually are aligned with Management's requirements and warrant the expenditure of funds allocated to I/S?
- Do you care whether the data in the Enterprise means the same thing to anyone who uses it, that messages can be cost-effectively transmitted and received whatever time of day or night or day of the year, and that business rules can be uniformly enforced throughout the Enterprise?
- Do you care whether changes to the Enterprise can be made with minimum time, disruption, and cost?
- Do you care whether I/S can produce "custom" implementations on demand, reducing their time-to-market to virtually zero?
If you care about any or all of these things, YOU ARE GOING TO DO ARCHITECTURE, because without Architecture, you cannot do ANY of these things.”
Architecture is an asset. You can save orders of magnitude more money and time, but you have to invest in Architecture to enable you to do something you otherwise are unable to do, namely: "Alignment", "Integration", "Change", and "Mass Customization".
Modeling techniques are the best way to efficiently manage enterprise assets. Powerful modeling approaches require a large range of modeling artifacts to be able to cover the entire scope of enterprise architectures. However, it is not always easy to know which modeling technique to use. The most common question asked by Business and IT architects when modeling is: “Where should I start?”. The usual answer is that there is no one starting point; it has to be defined on a project basis. This statement usually adds more confusion than it really brings any help to modelers.
The Zachman Framework is a powerful answer to these questions: by providing a global view of the multiple aspects of enterprise architecture, it offers a navigation tool that acts both as a starter and a compass for enterprise modelers. It provides a context in which Business and IT architects can build a flexible, consistent information system, in accordance with the strategy of their enterprise.
The Zachman framework can successfully be used as a tool for defining project scope, for checking project completeness, and as a learning tool for enterprise architectures.
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