The title “Zachman Framework” refers to The Zachman Framework for Enterprise Architecture. The initial framework, named A Framework for Information Systems Architecture, by John Zachman published in an 1987 article in the IBM Systems journal. The Zachman Framework is introduced as a framework, originated by and named after John Zachman, represented in numerous ways, see image. This framework is explained as, for example:
- a framework to organize and analyze data
- a framework for enterprise architecture
- a classification system, or classification scheme
- a matrix, often in a 6×6 matrix format
- a two-dimensional model or an analytic model
- a two-dimensional schema, used to organize the detailed representations of the enterprise.
Beside the frameworks developed by John Zachman, numerous extensions and/or applications have been developed, which are also sometimes called Zachman Frameworks, however they generally tend to be graphical overlays of the actual framework itself.
The Zachman Framework summarizes a collection of perspectives involved in enterprise architecture. These perspectives are represented in a two-dimensional matrix that defines along the rows the type of stakeholders and with the columns the aspects of the architecture. The framework does not define a methodology for an architecture. Rather, the matrix is a template that must be filled in by the goals/rules, processes, material, roles, locations, and events specifically required by the organization. Further modeling by mapping between columns in the framework identifies gaps in the documented state of the organization.
The framework is a logical structure for classifying and organizing the descriptive representations of an enterprise. It is significant to both the management of the enterprise, and the actors involved in the development of enterprise systems. While there is no order of priority for the columns of the Framework, the top-down order of the rows is significant to the alignment of business concepts and the actual physical enterprise. The level of detail in the Framework is a function of each cell (and not the rows). When done by IT the lower level of focus is on information technology, however it can apply equally to physical material (ball valves, piping, transformers, fuse boxes for example) and the associated physical processes, roles, locations etc. related to those items.
In the 1980s John Zachman had been involved at IBM in the development of business system planning (BSP), a method for analyzing, defining and designing an information architecture of organizations. In 1982 Zachman had already concluded that these analyses could reach far beyond automating systems design and managing data into the realms of strategic business planning and management science in general. It may be employed in the (in that time considered more esoteric) areas of enterprise architecture, data-driven systems design, data classification criteria, and more.
Information Systems Architecture Framework
In the 1987 article “A Framework for Information Systems Architecture” Zachman noted that the term “architecture” was used loosely by information systems professionals, and meant different things to planners, designers, programmers, communication specialists, and others. In searching for an objective, independent basis upon which to develop a framework for information systems architecture, Zachman looked at the field of classical architecture, and a variety of complex engineering projects in industry. He saw a similar approach and concluded that architectures exist on many levels and involves at least three perspectives: raw material or data, function of processes, and location or networks.
The Information Systems Architecture is designed to be a classification schema for organizing architecture models. It provides a synoptic view of the models needed for enterprise architecture. Information Systems Architecture does not define in detail what the models should contain, it does not enforce the modeling language used for each model, and it does not propose a method for creating these models.
Framework for enterprise architecture
In the 1997 paper “Concepts of the Framework for Enterprise Architecture” Zachman said that the framework should be referred to as a “Framework for Enterprise Architecture”, and should have from the beginning. In the early 1980s however, according to Zachman, there was “little interest in the idea of Enterprise Reengineering or Enterprise Modeling and the use of formalisms and models was generally limited to some aspects of application development within the Information Systems community”.
Zachman Framework Topics
The basic idea behind the Zachman Framework is that the same complex thing or item can be described for different purposes in different ways using different types of descriptions (e.g., textual, graphical). The Zachman Framework provides the thirty-six necessary categories for completely describing anything; especially complex things like manufactured goods (e.g., appliances), constructed structures (e.g., buildings), and enterprises (e.g., the organization and all of its goals, people, and technologies). The framework provides six different transformations of an abstract idea (not increasing in detail, but transforming) from six different perspectives.
It allows different people to look at the same thing from different perspectives. This creates a holistic view of the environment, an important capability illustrated in the figure.
Views of rows
Each row represents a total view of the solution from a particular perspective. An upper row or perspective does not necessarily have a more comprehensive understanding of the whole than a lower perspective. Each row represents a distinct, unique perspective; however, the deliverables from each perspective must provide sufficient detail to define the solution at the level of perspective and must translate to the next lower row explicitly.
Each perspective must take into account the requirements of the other perspectives and the restraint those perspectives impose. The constraints of each perspective are additive. For example, the constraints of higher rows affect the rows below. The constraints of lower rows can, but do not necessarily affect the higher rows. Understanding the requirements and constraints necessitates communication of knowledge and understanding from perspective to perspective. The Framework points the vertical direction for that communication between perspectives.
The current version (3) of the Zachman Framework categorizes the rows as follows www.zachman.com
- Executive Perspective (Scope Contents) – The first architectural sketch is a “bubble chart” or Venn diagram, which depicts in gross terms the size, shape, partial relationships, and basic purpose of the final structure. It corresponds to an executive summary for a planner or investor who wants an overview or estimate of the scope of the system, what it would cost, and how it would relate to the general environment in which it will operate.
- Business Management Perspective (Business Concepts) – Next are the architect’s drawings that depict the final building from the perspective of the owner, who will have to live with it in the daily routines of business. They correspond to the enterprise (business) models, which constitute the designs of the business and show the business entities and processes and how they relate.
- Architect Perspective (System Logic) – The architect’s plans are the translation of the drawings into detail requirements representations from the designer’s perspective. They correspond to the system model designed by a systems analyst who must determine the data elements, logical process flows, and functions that represent business entities and processes.
- Engineer Perspective (Technology Physics) – The contractor must redraw the architect’s plans to represent the builder’s perspective, with sufficient detail to understand the constraints of tools, technology, and materials. The builder’s plans correspond to the technology models, which must adapt the information systems model to the details of the programming languages, input/output (I/O) devices, or other required supporting technology.
- Technician Perspective (Tool Components) – Subcontractors work from shop plans that specify the details of parts or subsections. These correspond to the detailed specifications that are given to programmers who code individual modules without being concerned with the overall context or structure of the system. Alternatively, they could represent the detailed requirements for various commercial-off-the-shelf (COTS), government off-the-shelf (GOTS), or components of modular systems software being procured and implemented rather than built.
- Enterprise Perspective or (Operations Instances)
Focus of columns
In summary, each perspective focuses attention on the same fundamental questions, then answers those questions from that viewpoint, creating different descriptive representations (i.e., models), which translate from higher to lower perspectives. The basic model for the focus (or product abstraction) remains constant. The basic model of each column is uniquely defined, yet related across and down the matrix. In addition, the six categories of enterprise architecture components, and the underlying interrogatives that they answer, form the columns of the Zachman Framework and these are:
- Inventory Sets — What
- Process Flows — How
- Distribution Networks — Where
- Responsibility Assignments — Who
- Timing Cycles — When
- Motivation Intentions — Why
In Zachman’s opinion, the single factor that makes his framework unique is that each element on either axis of the matrix is explicitly distinguishable from all the other elements on that axis. The representations in each cell of the matrix are not merely successive levels of increasing detail, but actually are different representations — different in context, meaning, motivation, and use. Because each of the elements on either axis is explicitly different from the others, it is possible to define precisely what belongs in each cell.
Framework set of rules
The framework comes with a set of rules:
- The columns have no order : The columns are interchangeable but cannot be reduced or created
- Each column has a simple generic model : Every column can have its own meta-model
- The basic model of each column must be unique : The basic model of each column, the relationship objects and the structure of it is unique. Each relationship object is interdependent but the representation objective is unique.
- Each row describes a distinct, unique perspective : Each row describes the view of a particular business group and is unique to it. All rows are usually present in most hierarchical organizations.
- Each cell is unique : The combination of 2,3 & 4 must produce unique cells where each cell represents a particular case. Example: A2 represents business outputs as they represent what are to be eventually constructed.
- The composite or integration of all cell models in one row constitutes a complete model from the perspective of that row : For the same reason as for not adding rows and columns, changing the names may change the fundamental logical structure of the Framework.
- The logic is recursive : The logic is relational between two instances of the same entity.
The framework is generic in that it can be used to classify the descriptive representations of any physical object as well as conceptual objects such as enterprises. It is also recursive in that it can be used to analyze the architectural composition of itself. Although the framework will carry the relation from one column to the other, it is still a fundamentally structural representation of the enterprise and not a flow representation.
Flexibility in level of detail
One of the strengths of the Zachman Framework is that it explicitly shows a comprehensive set of views that can be addressed by enterprise architecture. Some feel that following this model completely can lead to too much emphasis on documentation, as artefacts would be needed for every one of the thirty cells in the framework. Zachman, however, indicates that only the fasts needed to solve the problem under analysis need be populated.
John Zachman clearly states in his documentation, presentations, and seminars that, as framework, there is flexibility in what depth and breadth of detail is required for each cell of the matrix based upon the importance to a given organization. An automaker, whose business goals may necessitate an inventory and process-driven focus, could find it beneficial to focus their documentation efforts on What and How columns. Whereas a travel agent company, whose business is more concerned with people and event-timing, could find it beneficial to focus their documentation efforts on Who, When, and Where columns. However, there is no escaping the Why column’s importance as it provides the business drivers for all the other columns.
Applications and influences
Since the 1990s the Zachman Framework has been widely used as a means of providing structure for Information Engineering-style enterprise modeling. The Zachman Framework can be applied both in commercial companies and in government agencies. Within a government organization the framework can be applied to an entire agency at an abstract level, or it can be applied to various departments, offices, programs, subunits and even to basic operational entities.
[Cambridge Technical Communicators (CTC)]