The TOGAF ADM is the result of continuous contributions from a large number of architecture practitioners. It describes a method for developing an enterprise architecture, and forms the core of TOGAF. It integrates elements of TOGAF described in this document as well as other available architectural assets, to meet the business and IT needs of an organization.
Relationship to Other Parts of TOGAF:-
There are two other main parts to TOGAF, besides the ADM:
- The Enterprise Continuum, described in detail in Part III: Enterprise Continuum. This is a "framework-within-a-framework" that provides context for the leveraging of relevant architecture assets and provides navigational help when discussions move between different levels of abstraction.
2. The TOGAF Resource Base, described in Part IV: Resource Base. This is a set of resources - guidelines, templates, checklists, and other detailed materials - supporting the TOGAF ADM.
The ADM and the Enterprise Continuum:-
As mentioned above, the Enterprise Continuum provides a framework and context for the leveraging of relevant architecture assets in executing the ADM. These assets may include architecture descriptions, models, and patterns taken from a variety of sources, as explained in Part III: Enterprise Continuum. At relevant places throughout the 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 the TOGAF Foundation Architecture (see Part III: Enterprise Continuum). 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.
The practical implementation of the Enterprise Continuum will often take the form of a repository that includes reference architectures, models, and patterns that have been accepted for use within the enterprise, and actual architectural work done previously within the enterprise. The architect would seek to re-use as much as possible from the Enterprise Continuum that was relevant to the project at hand. (In addition to the collection of architecture source material, the repository would also contain architecture development work-in-progress.)
The criteria for including source materials in an organization's Enterprise Continuum will typically form part of the organization's IT governance process.
The Enterprise Continuum is thus a framework (a "framework-within-a-framework") for categorizing architectural source material - both the contents of the architecture working repository, and the set of relevant, available reference models in the industry.
In executing the ADM, the architect is not only developing the end result of an organization-specific architecture, but is also populating the organization's own Enterprise Continuum, with all the architectural assets identified and leveraged along the way, including, but not limited to, the resultant enterprise-specific architecture.
Architecture development is an iterative, ongoing process, and in executing the ADM repeatedly over time, the architect gradually populates more and more of the organization's Enterprise Continuum. Although the primary focus of the ADM is on the development of the enterprise-specific architecture, in this wider context the ADM can also be viewed as the process of populating the enterprise's own Enterprise Continuum with relevant re-usable building blocks.
In fact, the first execution of the ADM will often be the hardest, since the architecture assets available for re-use will be relatively few. Even at this stage of development, however, there will be architecture assets available from external sources such as TOGAF, as well as the IT industry at large, that could be leveraged in support of the effort.
Subsequent executions will be easier, as more and more architecture assets become identified, are used to populate the organization's Enterprise Continuum, and are thus available for future re-use.
The ADM is also useful to populate the Foundation Architecture of an enterprise. Business requirements of an enterprise may be used to identify the necessary definitions and selections in the Foundation Architecture. This could be a set of re-usable common models, policy and governance definitions, or even as specific as overriding technology selections (e.g., if mandated by law). Population of the Foundation Architecture follows similar principles as for an enterprise architecture, with the difference that requirements for a whole enterprise are restricted to the overall concerns and thus less complete than for a specific enterprise.
It is important to recognize that existing models from these various sources may not necessarily be integratable into a coherent enterprise architecture. "Integratability" of architecture descriptions is considered in Architecture Integration .
The ADM and the Resource Base:-
The TOGAF Resource Base is a set of resources - guidelines, templates, checklists, and other detailed materials - that support the TOGAF ADM.
The individual sections of the Resource Base are described separately in Part IV: Resource Base so that they can be referenced from the relevant points in the ADM as necessary, rather than having the detailed text clutter the description of the ADM itself.