SOA and Enterprise architecture should not be confused with each Other

I have done an interview article for IT Web and iWeek. 

Here is the extract of the article:  (You can find the original article here)

Service Oriented Architecture (SOA) is still relatively poorly understood in South Africa and only a handful of large companies in the country have started to embrace the concept.

That's according to Ignus Geyer, principle architect at African Legend (AL) Indigo. He says that that the concept of SOA is often conflated with enterprise architecture, when the two terms cannot really be folded together.

“An enterprise architecture is a blueprint that organisations use to map out their business models, including how the people, processes, technology and data that drive the business interact with each other. Enterprise architecture essentially depicts how an organisation is structured and operates, allowing management to set out how the enterprise can most effectively achieve its objectives”, says Geyer.

It operates at a much higher level of abstraction than SOA, a concept that is geared towards resolving particular technology and business challenges in the modern enterprise, he adds. Enterprise architecture is technology-neutral.

SOA is an evolution from earlier concepts in software architecture and development, such as Web services, object oriented development and enterprise application integration. Its promise is to allow companies to reuse software components - or business services - across multiple applications, thereby easing systems integration, improving enterprise agility, aligning IT and business more closely together, and enabling faster software development.

The "architecture" in SOA is something of a misnomer, since SOA is a methodology or a technology framework rather than architecture, says Geyer. To explain the two concepts and how they fit together, Geyer gives the example of a company that plans to grow its product portfolio and customer base by acquiring other companies.

The enterprise architecture will detail at a high level how the organisational structure, data models, processes, technology and so on, enabling this strategy. SOA, by contrast, will serve as a key enabler for the strategy by setting out the methodology, standards and tools the organisation will use to integrate and reuse the assets of the companies it acquires, Geyer adds.

"SOA helps organisations to create, measure and understand the various models that compromise their enterprise architectures. It's a subset of enterprise architecture," he continues. "It enables companies to engineer and reuse building blocks that address specific business challenges rather than needing to create novel solutions to each problem."

Standards such as Business Process Execution Language (BPEL) and Business Process Modeling Notation (BPMN) play a critical role in bridging the gap between the blueprint provided by the enterprise architecture and the technology and processes that drive the business.

The BPEL language enables organisations to automate their business processes by orchestrating 'services,' the reusable building blocks of applications in SOAs. BPMN, meanwhile, is an established standard graphical representation that is used to specify process models in the context of SOA. BPMN ensures that business professionals and IT professionals in an enterprise are speaking the same language when working together on SOA projects.

Adopting SOA will demand that an organisation re-looks at its organisational model and brings about changes in the ways that people work and act, says Geyer. Putting the right tools and policies in place for SOA governance is critical to ensuring the success of SOA in an enterprise, he adds.

Gartner defines SOA Governance as "Ensuring and validating that assets and artifacts within the architecture are acting as expected and maintaining a certain level of quality." The right technology can allow organisations to automate and monitor SOA governance.