Overview Architecture Re-use ADM Constituents Structure of Part III
This section introduces the concept of the Enterprise Continuum, which sets the broader context for TOGAF, by explaining the different types and scopes of the architecture artifacts and assets that can be derived from it, and leveraged during its use.
The Enterprise Continuum is an important aid to communication and understanding, both within individual enterprises, and between customer enterprises and vendor organizations. Without an understanding of "where in the continuum you are", people discussing architecture can often talk at cross purposes because they are referencing different points in the continuum at the same time, without realizing it.
Any architecture is context specific; for example, there are architectures that are specific to individual customers, industries, subsystems, products, and services. Architects, on both the buy side and supply side, must have at their disposal a consistent language to effectively communicate the differences between architectures. Such a language will enable engineering efficiency and the effective leveraging of Commercial Off-The-Shelf (COTS) product functionality. The Enterprise Continuum provides that consistent language.
Not only does the Enterprise Continuum represent an aid to communication, it represents an aid to organizing re-usable architecture and solution assets. This is explained further below.
The simplest way of thinking of the Enterprise Continuum is as a "virtual repository" of all the architecture assets - models, patterns, architecture descriptions, and other artifacts - that exist both within the enterprise and in the IT industry at large, which the enterprise considers itself to have available for the development of architectures for the enterprise.
Examples of "assets within the enterprise" are the deliverables of previous architecture work, which are available for reuse. Examples of "assets in the IT industry at large" are the wide variety of industry reference models and architecture patterns that exist, are continually emerging, including those that are highly generic (such as TOGAF's own Technical Reference Model); those specific to certain aspects of information technology (such as a web services architecture, or a generic manageability architecture); those specific to certain types of information processing, such as e-Commerce, supply chain management, etc.; and those specific to certain vertical industries, such as the models generated by vertical consortia such as TMF (in the Telecommunicaitons sector), ARTS (retial), POSC (petrotechnical), etc.
The decision as to which architecture assets a specific enterprise considers part of its own Enterprise Continuum will normally form part of the overall Architecture Governance function within the enterprise concerned.
The TOGAF Architecture Development Method describes the process of moving from the TOGAF Foundation Architecture to an enterprise-specific architecture (or set of architectures). This process leverages the elements of the TOGAF Foundation Architecture and other relevant architectural assets, components, and building blocks along the way.
At relevant places throughout the TOGAF ADM, there are reminders to consider which architecture assets from the Enterprise Continuum the architect should use, if any. In some cases, from example in the development of a Technology Architecture, this may be TOGAF's own Foundation Architecture (see below). In other cases, for example in the development of a business architecture, it may be a reference model for e-Commerce taken from the industry at large.
TOGAF itself provides two reference models for consideration for inclusion in an organization's Enterprise Continuum:
However, in developing architectures in the various domains within an overall enterprise architecture, the architect will need to consider the use and re-use of a wide variety of different architecture assets, and the Enterprise Continuum provides a framework (a "framework-within-a framework", if you like) for categorizing and communicating these different assets.
The "Enterprise Continuum" is a phrase that denotes the combination of two complementary concepts: the "Architecture Continuum" and the "Solutions Continuum".
The immediately following section provides greater detail about the Enterprise Continuum. It first outlines the Architecture Continuum and Solutions Continuum separately, and then explains how they come together to form the Enterprise Continuum.
The remainder of Part III is structured as follows:
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