TOGAF® Version 9 - A Pocket Guide

Chapter 2
The Architecture Development Method

This chapter describes the Architecture Development Method (ADM), its relationship to the rest of TOGAF, and high-level considerations for its use. It also includes a summary of each phase within the ADM.

Topics addressed in this chapter include:

   An introduction to the ADM

   The phases of the ADM

   The objectives, steps, inputs, and outputs to the ADM phases

   Requirements Management during the ADM cycle

   Scoping the architecture activity

2.1    What is the ADM?

The ADM, a result of contributions from many architects, forms the core of TOGAF. It is a method for deriving organization-specific enterprise architectures and is specifically designed to address business requirements. The ADM describes:

   A reliable, proven way of developing and using an enterprise architecture

   A method of developing architectures on different levels4 (business, application, data, technology) that enable the architect to ensure that a complex set of requirements are adequately addressed

   Guidelines on tools for architecture development

2.2    What are the Phases of the ADM?

The ADM consists of a number of phases that cycle through a range of architecture domains that enable the architect to ensure that a complex set of requirements is adequately addressed. The basic structure of the ADM is shown in Figure 2.

Figure 2: The Architecture Development Method Cycle

The ADM is applied iteratively throughout the entire process, between phases, and within them. Throughout the ADM cycle, there should be frequent validation of results against the original requirements, both those for the whole ADM cycle, and those for the particular phase of the process. Such validation should reconsider scope, detail, schedules, and milestones. Each phase should consider assets produced from previous iterations of the process and external assets from the marketplace, such as other frameworks or models.

The ADM supports the concept of iteration at three levels:

   Cycling around the ADM: The ADM is presented in a circular manner indicating that the completion of one phase of architecture work directly feeds into subsequent phases of architecture work.

   Iterating between phases: TOGAF describes the concept of iterating across phases (e.g., returning to Business Architecture on completion of Technology Architecture).

   Cycling around a single phase: TOGAF supports repeated execution of the activities within a single ADM phase as a technique for elaborating architectural content.

Further information on iteration is given in TOGAF 9, Part III: ADM Guidelines and Techniques (see Chapter 4).

Table 3: Architecture Development Method Activities by Phase

ADM Phase

Activity

Prepare the organization for successful TOGAF architecture projects. Undertake the preparation and initiation activities required to meet the business directive for a new enterprise architecture, including the definition of an organization-specific architecture framework and tools, and the definition of principles.

Every stage of a TOGAF project is based on and validates business requirements.
Requirements are identified, stored, and fed into and out of the relevant ADM phases, which dispose of, address, and prioritize requirements.

Set the scope, constraints, and expectations for a TOGAF project. Create the Architecture Vision. Define stakeholders. Validate the business context and create the Statement of Architecture Work. Obtain approvals.

Develop architectures at three levels:

Business

Information Systems

Technology

In each case, develop the Baseline and Target Architectureand analyze gaps.

Perform initial implementation planning and the identification of delivery vehicles for the building blocks identified in the previous phases. Identify major implementation projects, and group them into Transition Architectures.

Analyze cost benefits and risk. Develop detailed Implementation and Migration Plan.

Provide architectural oversight for the implementation. Prepare and issue Architecture Contracts (Implementation Governance Board). Ensure that the implementation project conforms to the architecture.

Provide continual monitoring and a change management process to ensure that the architecture responds to the needs of the enterprise and maximizes the value of the architecture to the business.

2.3    The ADM in Detail

The following tables summarize the objectives, steps, and the inputs and outputs5 of each phase of the ADM cycle.

2.3.1  Preliminary Phase

The Preliminary phase prepares an organization to undertake successful enterprise architecture projects.

An overview of the phase is given below:

Objectives

Steps

To review the organizational context forconducting enterprise architecture

To identify the stakeholders, their requirements, and priorities

To confirm the commitment of the stakeholders

To identify and scope the elements of the enterprise organizations affected and define the constraints and assumptions; this is particularly important for large organizations where there may be a federated architecture environment

To define an organization's "architecture footprint"; that is, the people responsible for performing the architecture work, where they are located, and their responsibilities

To define the framework and detailed methodologies that are going to be used to develop the enterprise architecture in the organization; this is typically an adaptation of the ADM

To set up a governance and support framework to provide business process and architecture governance through the ADM cycle; these will confirm the fitness-for-purpose and ongoing effectiveness of the Target Architecture; normally this includes an initial pilot project

To select and implement supporting tools and other infrastructure to support the architecture activity

To define the constraining architecture principles

Scope the enterprise organizations impacted

Confirm governance and support frameworks

Define and establish enterprise architecture team and organization

Identify and establish architecture principles

Select and tailor architecture framework(s)

Implement architecture tools

Inputs

Outputs

TOGAF

Other architecture framework(s)

Business principles, business goals, and business drivers

Architecture governance strategy

IT strategy

Existing organizational model for enterprise architecture

Existing architecture framework, if any

Existing architecture principles, if any

Existing Architecture Repository, if any

Organizational model forenterprise architecture

Tailored Architecture Framework, including architecture principles

Initial Architecture Repository

Restatement of, or reference to, business principles, businessgoals, and business drivers

Request for Architecture Work

Governance Framework

2.3.2  Phase A: Architecture Vision

Phase A is about project establishment and initiates an iteration of the architecture development cycle, setting the scope, constraints, and expectations for the iteration. It is required in order to validate the business context and to create the approved Statement of Architecture Work.

Objectives

Steps

Obtain management commitment for thisparticular cycle of the ADM

Define and organize an architecture development cycle

Validate business principles, goals, drivers, and key performance indicators (KPIs)

Define, scope, and prioritize architecture tasks Identify stakeholders, their concerns, and objectives

Define business requirements and constraints

Articulate an Architecture Vision and valueproposition to respond to the requirements and constraints

Create a comprehensive plan in line with theproject management frameworks adopted bythe enterprise

Obtain formal approval to proceed

Understand the impact on, and of, otherparallel architecture development cycles

Establish the architecture project

Identify stakeholders, concerns, and business requirements

Confirm and elaborate business goals, business drivers, and constraints

Evaluate business capabilities

Assess readiness for business transformation

Define scope

Confirm and...