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Human Task Integration in Web Based Business Processes. Xue Bai COMS E6125 WEB-ENHANCED INFORMATION MGMT. A Groundwork Investigation. Outline. Business Process Execution Language, BPEL4People, WS- HumanTask Open problem Potential Directions. WS-BPEL.
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Human Task Integration in Web Based Business Processes Xue Bai COMS E6125 WEB-ENHANCED INFORMATION MGMT A Groundwork Investigation
Outline • Business Process Execution Language, BPEL4People, WS-HumanTask • Open problem • Potential Directions
WS-BPEL • Web Services Business Process Execution Language • Executable workflow language • Define formal specification of the “Business Processes” or “Workflows” • It’sthe combination of WSFL and XLANG • Standards: http://docs.oasis-open.org/wsbpel/2.0/wsbpel-v2.0.pdf • Drawback: lack of “human workflow” support, human interactions are not defined
BPEL4People • WSBusiness Process Execution Language for People • To address human interactions in BPEL by defining a new type of basic activity which uses human tasks as an implementation • This extension is based on the WS-HumanTaskspecification, as a bridge between BPEL and WS-HT • Specification: BPEL4People • White Paper: BPEL4People
WS-HumanTask • Introduces the definition of human tasks, including their properties, behaviors and a set of operations used to manipulate human tasks • human tasks are services which are implemented by people so as to allow the integration of humans in service-oriented application • Specification: WS-HumanTask
BPEL4People • The relationship among the various standards to support the BPEL4People Web services standards hierarchy
BPEL4People: An Introductory Tutorial • People activity, WS-HT specifies a human task
BPEL4People: An Introductory Tutorial • A business process, a sequence of BPEL activities
BPEL4People: An Introductory Tutorial • Workflow in a graph view
Open Problems • Significant difference: Unpredictable nature of human activities • Create a simple process to finish a business loan request to show scenario
Open Problems • 2 Companies, 2 Human Tasks, 4 Web Services • Exchange information and services, 9 steps RiskEvaluationReport LoanRepresentative: Tom RiskEvaluationRepresentative: Cathy EndUer: Peter decision RiskEvaluationReport request Information Information invoke Loan request invoke result
Open Problems • Two alternate case scenarios in step 7 (results) • Risk evaluation representative “Cathy” may need more information of end user “Peter”, report • “Cathy” may find some mistakes about the information from “Peter”, and she wants the “Loan Company”, to check the information again Tom Cathy Peter
Potential Directions • Professional process design • Avoid breaking down in the business process • Humans involved in the business process can communicate with each other • In the example described above, if “Cathy” finds some problems about the information provided by the “Loan Company”, she may contact the last human role in the business, “Tom” in this case
Potential Directions • Introduce the role of a “Proxy” • Monitor the data transmissions between web services • If a process needs to restart at some point other than the beginning, a copy of the data which is the input at that point will be delivered or coordinated from the “Proxy”