Services or subtasks? SOA and BPM may mean the same thing

We've been debating on these pages whether SOA and business process management go together, or if they're actually two very different disciplines.

Jason Bloomberg recently provided his take on the SOA-BPM discussion, saying that SOA and BPM are structurally the same. They may, in fact, be an example of "process isomorphism."

Jason is kind enough to provide a definition of isomorphism ("a mathematical concept that expresses a relationship between two concepts that are structurally identical but may differ in their respective implementations"). In an SOA context, process isomorphism means, hypothetically, "if you were to model a business process, and as a separate exercise, model the composition of services that implements that process, where those two models have the same structure, then they would be isomorphic."

Looking at SOA-BPM this way, then helps to establish a common language between business and IT, Jason points out:

"The business folks can be talking about processes, and the IT folks can be talking about SOBAs, and at a certain level, they're talking about the same thing... If process specialists want to think of Business Services as process subtasks, then they can go right ahead. Similarly, if technical implementers prefer to think of business processes as being compositions of Services, that's fine too. And best of all, when the BPM team draws the process specification on one white board and the SOA team draws the composition specification on another, the two diagrams will look exactly alike. If that's not business/IT alignment, then what is?"

Jason has hit upon something here, in that the perceived "rift" between SOA and BPM is more a product of semantics than actually structural differences between the two disciplines. SOA provides a collection of services that can be mapped to business processes as required.