The TOGAF ADM Framework is a method for developing an Enterprise Architecture and consists of the following phases. Each phase below is listed in the order that it should be followed through each iteration of the ADM.
The Preliminary Phase is used to describe the initiation and preparation activities that will be required to meet the specific business directives for a new enterprise architecture. The preliminary phase should include the definition of principles as well as the organisation specific architecture framework.
In summary the preliminary phase is used to prepare the organisation for undertaking successful enterprise architecture projects which includes:
- Understanding the business environment
- Engaging high-level management commitment
- Agreeing on the scope of the proposed architecture
- Establishing principles
- Establishing a governance structure
- Agreeing upon the method(s) that will be adopted.
Phase A – Architecture Vision
It is during the Architecture Vision or Phase A where the first iteration of the architecture process is initiated. It is also during Phase A where the scope, expectations and constrains of the project are set.
The Architecture Vision is used as the guide during the beginning of every architecture iteration to assist with the creation of the Architecture Statement of Work Document and Architecture Vision. The Statement of Architecture Work Documents are used to validate the context of the business.
Phase B – Business Architecture
When undertaking architecture work in any domain (Data, Application, Technology) it is prerequisite that there is knowledge pertaining to the Business Architecture. Therefore the first architecture activity that needs to be undertaken is gaining the knowledge of the business architecture.
On occasion, information pertaining to the Business Architecture may already be available in other business / organisational processes such as:
- Strategic Business Planning
- Enterprise Planning
- Business Process re-engineering
Phase C – Information System Architectures
Phase C is associated with two main architectures:
- Data Architecture
- Applications Architecture
When developing the architecture an architect must decide on which architecture to begin first; Application or Data?
In most instances it is usual to address both the data and applications architectures at the same time; however this may not always hold true depending on the scope of the project and any constraints.
If an architect had to choose which architecture to begin with, based on existing theory it would be wise to begin with the Data Architecture. However(!), due to practical considerations, it may mean that starting with the Application Architecture is more efficient.
Remember, that Phase C encapsulates two separate architecture domains (Data and Application). Therefore there are actually two areas / phases inside Phase C – Data and Application so there will need to be an iteration for both of these.
Phase D – Technology Architecture
The Technology Architecture Phase or Phase D is used to map any application components defined during the Application Architecture phase into a set of technology based components.
These technology components should be able to represent the hardware and software components which are already available on the market or components that are already configured within the organisation into technology platforms.
Phase E – Opportunities and Solutions
The Opportunities and Solutions Phase or Phase E is the first phase in the Architecture Development Methodology which is directly concerned with design and structure of how the target architecture will be achieved.
Phase F – Migration and Planning
During Phase F or the Migration Planning phase of the ADM the main focus is the development of a viable implementation and migration plan. The migration plan should be developed in conjunction with the project and portfolio managers.
Phase G – Implementation and Governance
The Implementation and Governance phase or Phase G is concerned with providing an architectural overview of the proposed implementation activities.
Providing an overview of the proposed implementation activities is to ensure that the activities are compliant with the target architectures.
Phase H – Architecture Change Management
During Phase H or the Architecture Change Management Phase the main goal is to ensure that the proposed architecture is able to achieve the original target as specified by the business.
The Architecture Change Management Phase should:
- Manage changes to the architecture in an orchestrated and cohesive manner
- Provide for continual monitoring of any changes in governance requests, new technology developments and any changes in the business environment
- If any changes do occur then the Change Management Phase should be used to determine if a new formal iteration of the architecture evolution cycle should be initiated.
Requirements management whilst not technically a phase within the ADM is vitally important. The Requirements Management is a process for the management of requirements throughout all phases of the ADM.