The Open Group Architecture Framework
(TOGAF) is a framework
for Enterprise Architecture
which provides a comprehensive approach to the design, planning, implementation, and governance of an enterprise information architecture
. The architecture is typically modeled at four levels or domains; Business, Application, Data, Technology. A set of foundation architectures are provided to enable the architecture team to envision the current and future state of the architecture.
Architecture and Architecture Framework Defined
specification of architecture (of software-intensive systems) may be stated as: "the fundamental organization of a system, embodied in its components, their relationships to each other and the environment, and the principles governing its design and evolution."
However TOGAF has its own view, which may be specified as either a "formal description of a system, or a detailed plan of the system at component level to guide its implementation", or as "the structure of components, their interrelationships, and the principles and guidelines governing their design and evolution over time."
An architecture framework is a toolset which can be used for developing a broad range of different architectures. It should:
- describe a methodology for defining an information system in terms of a set of building blocks
- show how the building blocks fit together
- contain a set of tools
- provide a common vocabulary
- include a list of recommended standards
- include a list of compliant products that can be used to implement the building blocks
TOGAF is such an architecture framework.
Enterprise Architecture Domains
TOGAF is based on four pillars, four architecture domains
- Business (or business process) architecture which defines the business strategy, governance, organization, and key business processes of the organization
- Applications architecture which provides a blueprint for the individual application systems to be deployed, the interactions between the application systems, and their relationships to the core business processes of the organization
- Data architecture which describes the structure of an organization's logical and physical data assets and the associated data management resources
- Technical architecture or Technology architecture which describes the hardware, software and network infrastructure needed to support the deployment of core, mission-critical applications
Architecture Development Method
The Architecture Development Method (ADM) is applied to develop an enterprise architecture which will meet the business and information technology needs of an organization. It may be tailored to the organization's needs and is then employed to manage the execution of architecture planning activities.
The process flow can be seen as an image located here: Architecture Development Cycle
The process is iterative and cyclic. Each step checks with Requirements. Phase C involves some combination of both Data Architecture and Applications Architecture.
Additional clarity can be added between steps B. and C. in order to provide a complete Information Architecture.
Performance Engineering working practices are applied to the Requirements phase, and to the Business Architecture, Information System Architecture, and Technology architecture phases. Within Information System Architecture, it is applied to both the Data Architecture and Application Architecture.
The Enterprise Continuum may be viewed as a "virtual repository" of all the architecture assets available to an organization. These include architectural models, architectural patterns, architecture descriptions, and other artifacts. These artifacts may exist within the enterprise and also in the IT industry at large.
The Enterprise Continuum consists of both the Architecture Continuum and the Solutions Continuum. The Architecture Continuum specifies the structuring of reusable architecture assets, and includes rules, representations and relationships of the information system(s) available to the enterprise. The Solutions Continuum describes the implementation of the Architecture Continuum by defining reusable solutions building blocks.
The Open Group
TOGAF has been developed by the Architecture Forum
of The Open Group
and continuously evolved since the mid-90’s. The latest version is 8.1.1, which is documented in detail in TOGAF 8.1 Enterprise Edition
The Forum is currently working on the TOGAF 9, which will be the next version of the three major TOGAF components – Architecture Development Method (ADM), Enterprise Continuum and Resource Base. The following themes have been identified for TOGAF Version 9 (expected late 2008):
- Evolution, not revolution
- Closer link to business
- Make TOGAF easier to use
The Open Group provides TOGAF free of charge to organizations for their own internal noncommercial purposes.
TOGAF certified tools
Alternative Enterprise Architecture Frameworks
- Zachman framework (IBM Framework from the 1980s, now claimed as a de facto world standard)
- DoDAF (United States Department of Defense Architectural Framework)
- FEAF (United States Office of Management and Budget Federal Enterprise Architecture)
- MODAF (United Kingdom Ministry of Defence Architectural Framework)
- AGATE (French Délégation Générale pour l'Armement Atelier de Gestion de l'ArchiTEcture des systèmes d'information et de communication)
- Service-Oriented Modeling Framework (SOMF) (Methodologies Corporation enterprise modeling framework)
- OBASHI (The OBASHI Business & IT methodology and framework)