Overview

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 Enterprise Continuum and Architecture Re-Use

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 re-use. Examples of "assets in the IT industry at large" are the wide variety of industry reference models and architecture patterns that exist, and are continually emerging, including those that are highly generic (such as TOGAF's own Technical Reference Model (TRM)); those specific to certain aspects of IT (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 like TMF (in the Telecommunications sector), ARTS (Retail), 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 Enterprise Continuum and the TOGAF ADM

The TOGAF Architecture Development Method (ADM) 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 - for 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:

• The TOGAF Foundation Architecture, which comprises a TRM of generic services and functions that provides a firm foundation on which more specific architectures and architectural components can be built; and a Standards Information Base (SIB) - an information base of relevant specifications and standards.
• The Integrated Information Infrastructure Reference Model (III-RM), which is based on the TOGAF Foundation Architecture, and is specifically designed to help the realization of architectures that enable and support the Boundaryless Information Flow vision.

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.

Constituents of the Enterprise Continuum

The "Enterprise Continuum" is a phrase that denotes the combination of two complementary concepts: the Architecture Continuum and the Solutions Continuum:

• The Architecture Continuum (The Architecture Continuum) offers a consistent way to define and understand the generic rules, representations, and relationships in an information system. The Architecture Continuum represents a structuring of re-usable architecture assets. The Architecture Continuum is directly supported by the Solutions Continuum (see below). The Architecture Continuum shows the relationships among foundational frameworks (such as TOGAF), common systems architectures (such as the III-RM), industry architectures, and enterprise architectures. The Architecture Continuum is a useful tool to discover commonality and eliminate unnecessary redundancy.
• The Solutions Continuum (The Solutions Continuum) provides a consistent way to describe and understand the implementation of the Architecture Continuum. The Solutions Continuum defines what is available in the organizational environment as re-usable Solutions Building Blocks (SBBs). The solutions are the results of agreements, between customers and business partners, that implement the rules and relationships defined in the architecture space. The Solutions Continuum addresses the commonalities and differences among the products, systems, and services of implemented systems.

The Enterprise Continuum in Detail 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.

Structure of Part III

Part III is structured as follows:

• Introduction (this section)
• The Enterprise Continuum in Detail
  • The Architecture Continuum
  • The Solutions Continuum
  • The Enterprise Continuum and your organization
• TOGAF Foundation Architecture: Technical Reference Model (TRM)
  • TRM Concepts
  • High-level breakdown
  • TRM in detail
  • Detailed platform taxonomy (Detailed Platform Taxonomy)
• TOGAF Foundation Architecture: Standards Information Base (SIB)
  • Introduction
  • Open Group standards
  • Using the SIB and linked resources
• TOGAF Integrated Information Infrastructure Reference Model (III-RM)
  • Basic concepts
  • High-level view
  • Detailed taxonomy

The TOGAF document set is designed for use with frames. To navigate around the document:

• In the main Contents frame at the top of the page, click the relevant hyperlink (Part I, Part II, etc.) to load the Contents List for that Part of the TOGAF document into the Secondary Index frame in the left margin.
  
  
• Then click in that Contents List to load a page into this main frame.
  
  

Downloads of the TOGAF documentation, are available under license from the TOGAF information web site. The license is free to any organization wishing to use TOGAF entirely for internal purposes (for example, to develop an information system architecture for use within that organization). A hardcopy book is also available from The Open Group Bookstore as document G063.