Monday, October 22, 2007

Pete Lacey's SOA definition

Read this SOA definition from Pete Lacey this morning and it almost makes sense...too bad it's not what most people mean.

So, then, what is SOA? For one thing, SOA is misnamed. It’s not an architecture in any sense of the word. It is, to use a Burton Group phrase, a mind set. It is the generally held belief that when implementing systems one should expose system functionality for general consumption directly from the network, as well as or instead of burying it behind a user interface. It is, as well, the belief that there is a great deal of value to be generated by retrofitting network accessibility into most existing systems. And it is the belief that this can only work if the means of doing so aren’t locked to a particular language, framework, operating system, vendor, or network architecture.

It's a bit hard to disagree with that as a good policy. However, having a bit of a linguistic bent, it makes me wonder if there isn't something fundamentally wrong with an acronym that is "misnamed". Mr. Lacey does suggest an alternative term for what he is describing: Network Oriented Computing. However doesn't that make it a worse definition of SOA (since the definition better fits another term)? It does. His final definition of SOA is "a technical approach to NOC that has a non-uniform service interface as its principle abstraction. Today, SOAP/WS-* is the chief implementation approach.". This is a better definition because it actually is an architecture. It also sits well next to ROA (Resource Oriented Architecture).

The killer final definition he offers is: "Business Service Architecture (BSA): An unnecessary term (also not an architecture) that tries to make the obvious something special. Aka, business analysis. Aka, requirements gathering." Reading this crystallized something important about why phrases like IT-Business alignment always bothered me- you align the IT systems with the business via requirements gathering. Now, maybe you are doing it at high level and want to give it a special name, but the dangers of abstract terms are that people can look like they are agreeing about how to do something, but really have completely different ideas about what they are concretely going to do.

Hmm, that might be a topic for another post.