Participants
Participants are responsible for performing the activities that comprise a process flow. Participants can be
- Organizations
- Roles
- Systems
Pools
Pools are containers for the sequence flow that is the responsibility of a participant.
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Pools
- Every participant has their own pool.
- Every end-to-end process is contained within a single pool. In other words, sequence flows cannot cross pool boundaries.
“Black box” pools—such as the Customer pool below—are used when the details regarding a participant’s process are unavailable or not important.
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A “black box” pool hides process details.
Lanes
Pools can be subdivided in a hierarchical fashion to add clarity regarding the responsibility for process activities.
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A pool may be subdivided into lanes corresponding to roles.
In the example above,
- The Enterprise pool is divided into Sales and Operations lanes.
- The Operations lane is subdivided into Warehouse and Delivery lanes.
Message Flows
Message flows define the flow of information between pools.
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Message flows represent the flow of information between pools.
Message flow can connect flow objects in different pools, a pool and a flow object in a different pool, or two pools.
Incoming message flows must be received before an activity starts. Outgoing message flows are sent upon the completion of an activity. In the example above,
- Message 1 must be received before Task A can begin.
- Message 2 is sent immediately upon the completion of Task C.
Initiating Processes with Messages
Processes are often started upon the receipt of a message. In the following example, a customer order triggers Company’s order fulfillment process.
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Initiating a process with a message flow