BPM versus SOA

There is a debate going on about the relationship between BPM (business process management) and SOA (service oriented architecture). Joe McKendrick reports on part of this debate. Also James Taylor adds a coin. Nick Malik plays his role as well and there are more.

To be honest, I never realized this subject as being ambiguous. But now I do. I love to join the debate.

• Isn't it fair to state that BPM is about a business process model and SOA about a way to abstract business functions (or process steps; sorry Steve, it's a matter of definition) from implementation?
• Isn't it fair to state that BPM is about the top level layer (business view) of inter-related composite structures?
• Isn't it fair to state the composite structures are modeled by SOA?
• Isn't it fair to state that BPM has a horizontal scope and SOA a vertical scope?
• Isn't it fair to state that SOA is the link between the business view (top level layer) and the IT-view (sub level layers)?

To me it makes sense to view the relationship between BPM and SOA in the way I stated above. And I go one step further. At the top level layer I prefer to use an EDA (event driven architecture) approach recognizing functional domains. So in my perspective it is essential to bring EDA to scene as well, where services at the top level layer equate to repeatable and predictable reactions to predefined business events. See the pictures below.

Figure taken from: How to implement a loosely coupled process flow (EDA)

Figure taken from: How EDA extends SOA and why it is important

I hope this posting is a valuable contribution to the BPM-SOA debate.