Three schools of thought on enterprise architecture exist, each with its own belief system (definitions, concerns, assumptions, and limitations). A novel taxonomy of these schools creates a starting point for resolving terminological challenges to help establish enterprise architecture as a discipline.
Scope & purpose:
Brief comparison among schools of thought:
If organisations are to survive the turbulence of today’s markets, they must learn to adapt and innovate. A survey by the Gartner and Forrester technology market consulting firms shows that current enterprise architecture practices, which are mostly based on the enterprise IT architecture school of thought, aren’t doing very well—they lack acceptance and are perceived as organisationally inconsiderate. It is recommended that the enterprises should have to move to more holistic ways of thinking if they wish to survive and flourish.
Source: James Lapalme, Three Schools of Thought on Enterprise Architecture, IT Professional Nov/Dec 2012.
Enterprise Architecture Framework is a set of assumptions, concepts, values, and practices that constitutes a way of looking at enterprise reality via views on (architecture) models. It offers a fundamental structure, serving as a scaffold for developing, maintaining, and using EA.
Zachman visualises the entire enterprise at one glance. All aspects are treated as equally important; should be described as simple, basic model.
The Open Group Architecture Framework (TOGAF) is a generic yet comprehensive methodological framework for developing enterprise architecture.
TOGAF Architecture Development Methodology (ADM)
TOGAF Architecture Content Framework
TOGAF Architecture Capability Framework
Gartner Methodology essentially stems from the META Group. It does not publish a formal framework or a process to do EA. Instead, its consultants guide enterprises in setting up a process by which EA can emerge from their business strategy.
Source: Stefan Bente et. al., Collaborative Enterprise Architecture, Morgan Kaufmann, Elsevier 2012. ISBN 9780124159341.
Introduction to ESARC:
ESARC Business & Information Reference architecture:
ESARC Business & Information Reference architecture metamodel:
ESARC Information Systems Reference architecture:
Source: Alfred Zimmermann et al, Towards Service-oriented Enterprise Architectures for Big Data Applications in the Cloud, IEEE International Enterprise Distributed Object Computing Conference Workshops, 2013.
- IT commercialisation
- Cross-enterprise collaboration
IT as Enterprise Integrator
Service-centric IT Ecosystem
Hybrid IT Portfolio
Five-phase approach (adapting ITIL methodology):
- Strategy: Our approach starts by identifying business needs and then defines the service capabilities and parameters necessary to support the business.
- Design: The enterprise identifies the necessary services and selects potential service providers. This process includes conventionally provided in-house services, but mainly focuses on external service providers.
- Implementation: In service-based IT, implementation includes negotiating and contracting for services, followed by assembly (or integration) of those services.
- Operation: The ongoing maintenance of business and technical relationships with service providers helps account for changes in the business and technology landscapes.
- Continuous improvement: The final phase is an ongoing effort to manage relationships with service providers to maximize business benefit. Efforts in this phase include assessing risks and devising mitigation strategies to protect against service disruptions or failures.
Source: Jamie Erbes et al, The Future of Enterprise IT in the Cloud, IEEE Computer, May 2012.