Janette Wong, a long-time IBMer who is now an independent consultant working as a solutions architect, discussed the use of workflow patterns in modeling business requirements and turning these into executable processes.
She used an example of an “authorization” business requirement, where manager can create confidential requests, and transfer those confidential requests to others. This can be matched to the standard role-based distribution pattern, which is fine for modeling, but then needs to be mapped to an implementation platform: in this case, some combination of WebSphere Process Server (WPS), LDAP or other directory service for user authentication and authorization, a workflow client application for human task management, and any other data sources that include user/role information. This multi-system implementation requires not only a conceptual mapping of the process and roles, but also actual integration between the systems that house the information. WPS provides instance-based authorization roles, then needs to bind that to the other sources at runtime in order to populate those roles; it doesn’t automate the solution, and in fact only provides a small amount of assistance in getting to that mapping. This is complicated further by role and authorization information that is spread out over multiple systems, particularly existing legacy systems; the business may think of the roles as being encapsulated in one of these other systems, which then needs to be mapped into the executing process.
She also discussed the requirement of a multi-item Inquiry, where multiple sub-inquiries will be created from the main inquiry (such as fraud investigations), and the exact number is not know at design time. This matches to the multiple instances without a priori runtime knowledge pattern, where you have multiple parallel sub-tasks that start and end independently, although the master activity has to wait for all children to complete before proceeding. This is similar to what we are seeing emerging in many case management implementations, where the parent activity is really the case itself, and the child tasks are those activities that the case workers initiates in order to move towards case resolution.
Wong observes that in spite of the length of time that BPM systems have been around, the larger patterns are not well supported by many of the systems although they are prevalent in real-world situations. She talked about the need for better design in process modeling tools, so that it is more obvious how to use the tools to implement these common, but complex, workflow patterns.