The Workflow Engine manages the process instance lifecycle, executing activity instances and evaluating transition rules. During the process instance lifecycle, the Workflow Engine will continue to respond to events, such as the completion of a task, which tell it to resume the execution of a process instance. The Workflow Engine creates tasks instructing users on the work that needs to be completed manually, and evaluates the allocation strategy to determine which users should be assigned these tasks. The Workflow Engine also creates notifications for users to inform them of the progress or status of a workflow process instance.
The Workflow Engine manages each process instance until the end process activity for that instance is reached. The execution of this activity indicates the completion of the process instance. If the workflow process instance fails, the workflow engine will record information about the failure. A workflow administrator can then use this information to retry the workflow process instance from the failure point.
For further details on the Workflow Engine see Workflow Engine and Process Enactment.