Overview#
This content relates to the TOGAF Standard. The following represent a set of notes I created while originally studying the TOGAF Standard. They are not intended to be an exhaustive summary, but an overview of some of the main points.
The Open Group Architecture Framework (TOGAF) is a framework for the development and management of enterprise architectures. (See Purpose for some rationale as to why this is important)
It is a best practice framework that provides a structured approach for Enterprise Architecture:
- It provides an Enterprise Architecture Framework to develop any kind of architecture in any context
- The framework has been developed a collaborative effort through a community.
- It describes a standard cycle of change used to plan, develop, implement, govern and change an architecture. This is described further in adm.
- Describes the building blocks within an enterprise that can be used to fulfil business capabilities and deliver services.
Consider the definition of Enterprise Architecture, It is made up of 2 separate words to distinguish the different roles of the architect.
Definition of Enterprise#
An Enterprise is any collection of organisations that have a common goal.
- This could be a whole Enterprise or one or more specific areas or business units.
- The Architecture could span multiple Enterprises
- It is considered to be a System
- The Enterprise scope may include suppliers, partners and customers
- An Enterprise may develop and maintain serveral different and independent Enterprise Architectures (see also Partitioning)
Definition of Architecture#
The TOGAF Standard enhances the ISO/IEC/IEEE 42010:2011 terminology
- The fundamental concepts or properties of a
system in its environment embodied in its elements,
relationships and in the principles of its design &
evolution.
(Source: ISO/IEC/IEEE 42010: 2011)
- The structure of components, their
interrelationships & the principles and guidelines
governing their design & evolution over time.
(Source: The Open Group TOGAF® Standard —
Introduction and Core Concepts)
Architecture Domains#
The TOGAF standard divides an Enterprise Architecture into 4 Different domains:
- Business Architecture - Defines the key business strategy, governance, organisation and key business processes
- Data Architecture - Describes the structure of an organisation’s conceptual, logical & physical data assets, data management resources
- Application Architecture - Provides a blueprint for the individual applications to be deployed, their interactions and their relationships to the core business processes of the organisation.
- Technology Architecture - Describes the digital architecture and logical software and hardware components and capabilities and standards that are required to support the deployment of business, data and application services.
Tailoring#
The generic TOGAF framework can be tailored and integrated with other frameworks.
I find the documentation and approach to this to be not well defined and the approach to tailoring is left to the practitioner. This leads to different view and can be seen as a way of covering up the prescriptive nature of TOGAF and trying to avoid the fact that it can be onerous to adopt.
TOGAF Architecture Development Method (ADM) TOGAF uses a “crop circle” diagram to show the progress of the different phases of the ADM.
Prior to commencing the ADM, the Preliminary phase should be completed, which will provide the framework and principles for the ADM. The phases may occur in parallel.
The circle theme is used to show the possible iterations of the architecture over time.
Requirements are in the centre as they will be updated and managed throughout the ADM phases.
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Purpose The primary purpose of Architecture Principles are:
Enable decision-making - it is important to set precedence during trade-off discussions and authority of tie-breaking if it must occur Align the enterprise - principles take subjectivity and bias out of the equation and drive critical conversations that are objective and aligned to the enterprise’s values Governance - how will the enterprise ensure that the right decisions are surfaced at the right time and with the right decision-makers, and, moreover, how to monitor the decisions and approach taken to arrive at the decision? Values and Culture - provide a better understanding about the enterprise’s culture and values; provide an approach and insight into how well the enterprise reacts to change Characteristics The following are some primary characteristics of Architecture Principles:
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Architecture Abstraction The concept of abstraction is a means to enable reasoning about an Architecture. Dividing a problem into smaller problems is a common approach to making an Architecture easier to model and create solutions for.
We can have one or more of the abstraction levels at each of the Strategic, Segment or Capability Architecture.
Introduction We can consider multiple simple questions in order to structure the approach to abstraction:
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Architecture Board The cross-enterprise architecture board is the highest level of architecture governance and is represnted by architecture stakeholders.
Role The Group of executives responsible for the review and maintenance of the architecture and to oversee the implementation of the strategy within Phase H - Architecture Change Management of the ADM. Possesses identifiable and articulated responsibilities, decision-making capabilities, remit and authority limits. Distinguishes between local (domain experts, line responsibility) and global (organisation-wide responsiblity) representatives in larger enterprises Scope may be Global, Regional or Business Line General Responsibilities The board is reponsible and accountable for achieving different goals:
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Architecture Capability The Enterprise Architecture is a business capability that supports 4 different types of business capabilities:
Architecture to Support Strategy Architecture to Support Portfolio Architecture to Support Projects Architecture to Support Solution Delivery Overview Posseses organisation structures with roles, responsibilities, skills and processes for Enterprise Architecture work. Treated like any other operational unit within the business. Establishes management capabilities for the architecture capability.
Purposes Purpose Capability Description Architecture to Support Strategy Provide Target Architecture and Roadmaps Change & synergies, governance Multiple programmes and portfolios Architecture to Support Portfolio Ensure alignment, synergies between architectures and governance Single portfolio of projects Support of Cross-functional and multi-phase architectures Architecture to Support Projects Integration between projects Integration between projects Value and Compliance per project Support the project delivery method Architecture to Support Solution Delivery Support the solution deployment for an architecture Governance Framework for change Single project or a significant part of a project Architecture to Support Strategy Provide end-to-end Target Architecture Develop Roadmaps for change over a period of 3 to 10 years
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Governance Overview Within TOGAF the focus is on Architecture Governance and how it supports other forms of governance within an enterprise.
Definition Given the focus on architecture governance within TOGAF, we can define governance as the system by which the current and future state are directed and controlled.
A committed and hierarchical decision-making process with a defined structure of relationships to direct and control the enterprise to achieve stated goals. Enables the equality of concerns and transparency (making sure all Stakeholders concerns are reflected), protecting the rights and interests of the business. It can be used to drive a set of behaviours controlled via measurements and metrics. Customisation A customised governance approach should define - How, When, Why and What?
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Architecture Partitioning Overview The TOGAF standard provides a framework for partitioning an architecture into different components.
Approach A divided subset of an Architecture facilitates its development and management. A specific form of abstraction.
Defined boundaries, governance and ownership This may lead to serveral architecture partions One owning team Architecture are partitioned such that there is a single team owning the Architecture Multiple Architecture Partitions A single team may own multiple partitions, but a single Architecture cannot be owned by multiple teams. The team will execute the ADM to define, govern and realise the Architecture. Adopt a partitioning model that reflects the Enterprise Operating Model. Benefits The theory is that partitioning will simplify the development and management of Architectures - Note if this is not the case the review the approach and alignment to the Enterprise Operating Model.
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