SOA: It's The Business Stupid!
Here is an edited subset of what I said on that internal thread on my continuing fustration about how technolgyu vendors trying to sell products have hijacked the term SOA. It's NOT about technology at all!
My friend Michele Bustamente, while I was tech-editing her O’Reilly WCF book, brought up this differentiation. While I think there is a differentiation, I am reluctant to call it “little SOA/Big SOA.” SOA is itself an architectural style that SOA/Software Architects use to create Service-Oriented “Services.” This is what you (and she) are calling “little SOA.”
However, just creating these services without business goals in mind, In my experience, just creates technology services by the IT/tech folks that are not reusable and show diminished business value. They meet immediate needs but not more. We call this “Bottom Up SOA.” On the other hand, big bang, “Big SOA” has an enterprise create a huge central SOA committee, take years to analyze all the business processes in the enterprise before rolling out a service. This is called “Top Down SOA.” This doesn’t work so well either, in my experience. Microsoft, on the other hand, as well as what I am promoting, is called “Middle Out SOA” also known as “Real World SOA.” In this style, you start with a focus on business process but as soon as you identify one service candidate, you do an Agile/Iterative combination of top down/bottom up for that ONE service and then you go on to the next and the next…
SOA has very little value as a technology driver. That is why SOA has had a lot of massive hype and failures; the term has been hijacked by technology vendors that wanted to sell both products and development tools in the guise of “Business Process Management.”
SOA has value only when applied from a business perspective. The primary goal of SOA is to align the business world with the world of IT in a way that makes them more effective. Period. Technology is only significant in the delivery phase and if we hit customers up with [indert any product here] without understanding the business drivers and processes, not only are we not doing SOA but we continuing to hype technology as the answer, and further disappointing customers with yet “another wave” of application integration technology with different products than the last time.