The SOA Elevator Speech
Here are some notes from a "brown bag" talk that I am preparing for our IT staff, many of whom are died-in-the-wool mainframe COBOL programmers. This talk will be far more evangelical then technical, and I hope that it will de-mystify SOA for some. I'm sure many of you will say "Duh!" when you read some of the points, but you'd be surprised how many folks just don't get it (yet).
I like the following definition of SOA from a paper by Bernhard Borges, Kerrie Holley and Ali Arsanjani, but it's a bit over-the-top as an introduction:
SOA is the architectural style that supports loosely coupled services to enable business flexibility in an interoperable, technology-agnostic manner. SOA consists of a composite set of business-aligned services that support a flexible and dynamically re-configurable end-to-end business processes realization using interface-based service descriptions.
I think it works better if I break down the definition as follows:
SOA is an architectural style that encourages the creation of loosely coupled business services
Loosely coupled services that are interoperable and technology-agnostic enable business flexibility
An SOA solution consists of a composite set of business services that realize an end-to-end business process
Each service provides an interface-based service description to support flexible and dynamically re-configurable processes
It's not as concise as the original, but I think it's a bit easier to swallow.