The Essense of SOA

Anne Thomas Manes’ recent article proclaiming the death of SOA has started a firestorm across many SOA and IT-related blogs and forums. I wrote about it here. In the post, Anne refers to the severe disillusionment some feel towards the over-hyped term, “SOA”, and proposes we drop the term altogether and simply refer to the core concept as “services”.

The term “SOA” is at the same time ubiquitous and ambiguous. So much energy has gone into molding it into a marketing story that it seems no two people share the same definition.. The truth is, SOA is really just a simple evolution in IT development strategy. I believe the essence of SOA is building software components as “interchangeable parts”, an idea preceding Eli Whitney himself. It is evolutionary (not revolutionary), because we’ve tried to do this for decades, culminating in object oriented and component-based software development. SOA is simply the next stepping stone, which loosens the chains of platform and vendor lock-in, catalyzed by internet and XML-based standards. It’s still about interchangeable parts, components that can be recombined and reused to either build new systems, or rapidly change existing ones. And it’s a superior strategy even if you don’t plan to reuse or recombine, because componentized systems are easier to build, manage, troubleshoot, and support.

In the software industry, I believe we are travelling a similar path as other industries, and finding that interchangeable parts are easy to design in the small, but exponentially more difficult to design in the large. Wiper blades and radios are easily replaced in your car. But I would just love to install a new hybrid-electric engine in my beloved ’96 Jeep Cherokee. Interchangeable parts on such a grand scale are much more problematic. I’m sure there’s marketing mechanics at work here, too. GM wraps their latest electric engine in the Chevy Volt, available next year for $42,000. They don’t want to sell just an engine.

So, I think the term we use to describe the concepts behind SOA is less important than agreeing on the core, underlying essence of SOA. I believe this to be extending the idea of “interchangeable parts”. Personally, I find myself avoiding the term “SOA” more and more, perhaps in a subconscious effort to avoid the pained or befuddled look on those faces in the room. Instead, I gravitate towards the term “service” or “service oriented”. Above all, we need to understand and accept that we are not revolutionaries. We are just carrying forward what others have already set in motion. By communicating this point, we gain credibility in our conversations with business people who control budgets. The alternative is to position this concept as “the next big thing”, something business people seem to immediately distrust.

Is SOA Dead?

Burton Group analyst and SOA guru Anne Thomas Manes recently blogged that “SOA is Dead” (http://apsblog.burtongroup.com/2009/01/soa-is-dead-long-live-services.html), referring to the disillusionment and even disgust some feel towards the over-hyped term. But she was referring just to the term SOA, not the concept itself. On the contrary, service orientation has seemed to find firm roots in diverse areas such as mashups, RIA, BPM, cloud computing, and others.

I completely agree that service orientation is here to stay. But I don’t agree that the term SOA is going away any time soon. We are in the typical “trough of disillusionment” Gartner speaks about, as a huge wave of over-hype sets high expectations for a technology. Industry buys into the vision, then slowly comes to realize it is not a silver bullet. Hard work is still to be done to extract the benefits of the new technology. When so many people express disappointment in a technology, negative momentum builds, and soon a consensus develops that the new technology is a failure at best, and evil at worst. Such is the case with SOA.

To be sure, some technologies never fully emerge from the trough. Artificial Intelligence and Object Databases are two examples that never achieved wide-spread adoption after huge early stage hype. Others fare much better, like EAI and even Java. I remember the early Java days working at MCI circa 1997. Despite huge investments including the best consultants Sun had to offer, projects were massively under-performing, or even failing altogether. But the gradual maturation of the platform and supporting tools pulled Java from the trough of disillusionment to eventually make it the most popular programming language ever.

Anne concludes by saying that we need to move away from the term SOA and simply use the term “services”, since that is the core foundation of the concept. I think that’s fine for the time being. In fact, I’ve recently found myself using the term “service orientation” instead of SOA anyway. But I believe this is a temporary diversion. Eventually, market noise will settle down, and we in the software industry will finally develop a consensus on what this concept really is. When that happens, I believe, it will mark the emergence from the trough of disillusionment, and the return to calling this concept “SOA” once again, without fear of scorn.

See my related post here.