Thursday, December 31, 2009

An Update on the BPEL4People & WS-Human Task Standards


The BPEL specification focuses on business processes, the activities of which are assumed to be interactions with Web services with no additional prerequisite behavior. But the spectrum of activities that make up general purpose business processes is much broader. People often participate in the execution of business processes introducing new aspects, such as human interaction patterns. Workflow tools already cater for the orchestration of user interactions.


User interactions range from simple scenarios, such as manual approval, to complex scenarios where data is entered by the user. Imagine a bank’s personal loan process. This process is made available on the internet site of the bank using a web interface. Customers can use this interface to enter the data for their loan approval request and to start the approval process. The process performs some checks, and eventually informs the customer whether his or her personal loan request has been approved or rejected. Processing is often automatic and does not require any human involvement. However, there are cases that require bank staff to be involved. An example of such a case is if the online check of a customer’s creditworthiness returns an ambiguous result. In this case, instead of declining the request automatically, a bank clerk could check the request and determine whether to approve or decline it. Another example would be if a request exceeds the amount of money that can be approved automatically. In this case, a manual approval step is required, in which a member of the “approvers” group either approves or declines the request.

User interactions in business processes are not limited to approval steps. They also may involve data. An example of a user interaction that involves data is when an e-mail from an employer is manually attached to the process instance, or when the summary of an interview with an applicant is keyed into the process via a simple form or custom-built application.

To support a broad range of scenarios that involve people within business processes, a BPEL extension is required.

BPEL4People is defined in a way that it is layered on top of the BPEL language so that its features can be composed with the BPEL core features whenever needed. We envisage that additional BPEL extensions may be introduced which may use the BPEL4People extension introduced here.

BPEL4People is the WS-BPEL Extension for People as proposed in a joint white paper by IBM and SAP in July 2005.

In June 2007, Active Endpoints, Adobe, BEA, IBM, Oracle and SAP published the BPEL4People and WS-HumanTask specifications as a follow-up to the whitepaper, describing how human interaction in BPEL processes can be performed.

The OASIS WS-BPEL Extension for People (BPEL4People) Tecnical Committee is working on standardizing the BPEL4People and WS-HumanTask specifications.

Click here for a very engaging podcast that describes the inner workings of Technical Committee’s (something you usually don’t hear much about), describes the work the OASIS TC has recently accomplished and articulates the grand vision for business process management (BPM) and workflow that the committee has been working on.

I strongly encourage you to listen to this podcast. You’ll hear how some the of most important thought-leaders in the IT world, including IBM, SAP, Oracle, Microsoft, TIBCO and Active Endpoints are discussing BPEL and BPEL4People.