The image shows the relationships among the BPEL components, including:
Oracle BPEL Server (upper left side), which interfaces with the Task Service and Task Assignment Service. The Task Assignment Service offers services to route, escalate, and reassign tasks. The Task Assignment Service communicates with the Notification Service. The Notification Service sends notifications to users by e-mail, voice, pager, fax, or SMS). The Task Assignment Service also communicates with the Task Metadata Service. The Task Metadata Service exposes operations to retrieve metadata information related to a task.
The Task Service communicates with the User Metadata Service, Identity Service, and Task Metadata Service. The Task Service provides persistence and exposes operations to update a task, complete a task, escalate and reassign tasks, and so on. The User Metadata Service manages metadata related to workflow (user work queues, preferences, vacation, and delegation rules). The Identity Service provides user/group/role lookup, user authentication, authorization, and organization hierarchy. The Identity Service has three possible user directory types: Oracle Internet Directory, JAZN XML, and LDAP, Custom.
Worklist application (upper right side) enables Web application to search for tasks, view tasks, act on tasks. The Worklist application communicates with the Task Query Service, which queries tasks for a user based on keyword, category, status, business process, attribute values, task history information, and so on. The Task Query Service communicates with the User Metadata Service and Identity Service (described above). The User Metadata Service communicates with the Runtime Config Services, which provide methods for managing metadata used in the task service runtime environment. The Runtime Config Services communicate with the Identity Service (described above).