Kimbo:
Data Flow Diagram ARE a process modeling technique! They are a process modeling technique that shows data flows. A circle (or oval) on a Data Flow Diagram labled "Calculate Sales Tax". What do you think that is?
Actually,data flow diagrams, as popularized by the Yourdon people, do not have to have data flows. They can instead show flows of school buses, pizzas, flying saucers, midgets, processed corn, beer, wine, etc., etc.
Sandy:
Process modeling of a large scope business system requires that the BA be guided through a logical partitioning to achieve an effective decomposition which is needed to handle the complexity. So, how does BPMN guide a BA in performing such partitioning?
Good question Tony. BPMN is a notation - it doesn't control (or constrain) the types of diagrams a BA actually produces. There are many ways that business processes can be modelled, from different perspectives and at different levels of detail. I have often modelled processes from a higher-level to lower-level of decomposition using BPMN notation in a variety of diagram types.
The advantages that BPMN offer are the additional information that can be modelled - such as triggering events, cycles, conditions that influence or direct process flows, etc. that DFD does not. I also use DFDs when I want to focus on exchange of data - they just don't have the full set of information that I need for as-is or to-be business models, so I wouldn't recommend them for that purpose.
Sandy
Tony / Sandy,
I've always thought that BPMN merges the DFD stream and other process notation streams like UML activity diagrams.
As a side note, it is possible to use BPMN to write DFDs although I'm not sure why anyone would because BPMN is way more expressive.
Kimbo
You said: I have often modelled processeom a higher-level to lower-level of decomposition using BPMN notation in a variety of diagram types.
Sandy, there is a currently popular book on BPMN that says that BPMN allows for any level of decomposition. However, no mention is made of the "work horse" of decompostion - partitioning. For more complex systems, logical, natural partitioning is required to generate an effective decompostion. So, the $64 question is how does BPMN actually guide a BA in performing a partitioning?
On-line I have"talked" with a lot of people who say that BPMN allows for deep decomposition, but none has yet been able to answer my question.
Kimbo: Your right, a BA can create a Data Flow Diagram using BPMN. But a DFD by any other name is still a DFD.
brought to you by enabling practitioners & organizations to achieve their goals using: