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What's up at OMG

Busy week at OMG as usual. The BPDM team presented the latest news on the status of the BPDM; and it seems to have come a long way in a few months.

There is something of a fracas about the relationship between BPMN and BPDM: is BPMN 'only' a notation or does it have some semantics. This whole thing was news to the BPMN team as they (including me) were blithely assuming that we were trying to define a language. For us, the major issues seem to revolve around the execution semantics of a BPMN diagram; for others, it is only a diagram notation and we needn't worry our little heads about execution. One might guess where that went!

The BPMN effort does seem to be a bit stuck right now. Personally, I think that the issue is that we are trying to have it both ways: have an easily understood execution semantics and allow the business modeler to do whatever and however he/she likes. The image is one of sharp scissors: do we give the modeler sharp scissors in the knowledge that they might cut themselves? In my opinion, there is a difference between having the sharp edge of the scissors on the outside or the inside of the blades. Some of the most basic features of BPMN (particularly the merges) are downright dangerous.

There is also an initiative to develop a UML profile oriented towards modeling SOA systems. Unfortunately I have not had time to look at it; but it should be a good idea.

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