Zachmanフレームワーク
Zachmanフレームワークはエンタープライズ分野向けのオントロジーであり、事業体を形式的・構造的な形で捉え(ビュー・モデル)、定義するためのエンタープライズアーキテクチャフレームワークである。オントロジーは2次元の分類スキーマになっており、昔から用いられている2つの分類法の組合せで作られている。1つ目の軸は基本的な疑問文(5W1H)で、2つ目の軸は哲学上の概念であり抽象的な概念の具体化を意味する具象化(Reification)をもとに作られている。
Zachmanフレームワークは、記述の対象となる情報の収集・管理・使用について特定の手法や手順に依ったものではなく、方法論ではない。Zachmanフレームワークはむしろ、アーキテクチャ上の成果物(言い換えると設計文書、仕様、モデル)を整理するための分類体系であり、成果物のターゲットとなる人(たとえば事業のオーナーや起業家)と解決すべき特定の課題(たとえばデータや機能性)の双方を考慮したものと言える。
Zachmanフレームワークという名前は、1980年代にIBMでこの概念を最初に開発したJohn Zachmanにちなんで命名されたものである。開発された後、数回の改訂がされている。
本記事のタイトルである"Zachmanフレームワーク"は、2021年時点でThe Zachman Framework for Enterprise Architectureの最新版であるバージョン3.0のことを指している。Zachmanフレームワークは、30年間におよぶ歴史の中で以下のように発展してきた。
最初期のフレームワーク。"A Framework for Information Systems Architecture"という名前で、1987年にJohn ZachmanがIBM Systems journalで発表したもの。
1987年の版を、1990年代に拡張してThe Zachman Framework for Enterprise Architectureと改称したもの。
その後のZachmanフレームワークで、Zachman Internationalから業界標準として提示されているもの。
In other sources 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 6x6 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.
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 simple and 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 not 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.
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.
In the 1992 article "Extending and Formalizing the Framework for Information Systems Architecture" John F. Sowa and John Zachman present the framework and its recent extensions and show how it can be formalized in the notation of conceptual graphs. Also in 1992:
John Zachman's co-author John Sowa proposed the additions of the Scope perspective of the `planner' (bounding lists common to the enterprise and its environment) and the Detailed Representation perspective of the `sub-contractor' (being the out of context vendor solution components). The Who, When and Why columns were brought into public view, the notion of the four levels of metaframeworks and a depiction of integration associations across the perspectives were all outlined in the paper. Keri Anderson Healey assisted by creating a model of the models (the framework metamodel) which was also included in the article.
Later during the 1990s
Methodologists like Clive Finkelstein refocused on the top two framework rows which he labeled Enterprise Engineering and has one of the most successful methods for converging the business needs with information engineering implementation, and determining a logical build sequence of the pieces.
In the 1997 paper "Concepts of the Framework for Enterprise Architecture" Zachman explained 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".
In 2008 Zachman Enterprise introduced the Zachman Framework: The Official Concise Definition as a new Zachman Framework standard.
Since the 1990s several extended frameworks have been proposed, such as:
Matthew & McGee (1990) extended the three initial perspectives "what", "how" and "where", to event (the "when"), reason (the "why") and organization (the "who").
Evernden (1996) presented an alternative Information FrameWork.
The Integrated Architecture Framework developed by Capgemini since 1996.
Vladan Jovanovic et all (2006) presents a Zachman Cube, an extended of the Zachman Framework into a multidimensional Zachman's Cube.
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 increasingly detailed views or levels of abstraction 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.
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.
In the 1997 Zachman Framework the rows are described as follows:
Planner's View (Scope) - 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.
Owner's View (Enterprise or Business Model) - 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.
Designer's View (Information Systems Model) - 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.
Builder's View (Technology Model) - 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.
Subcontractor View (Detailed Specifications) - 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.
Actual System View or The Functioning Enterprise
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:
What :データ記述
How :機能記述
Where :ネットワーク記述
Who :人間記述
When :時間記述
Why :動機記述