QuickStudy: Business Process Execution Language (BPEL)
Computerworld - For its advocates, Business Process Execution Language promises to be the capstone in the Web services standards stack that makes Web-based commerce work. It was designed to integrate a variety of applications that are run to achieve a particular business objectiveand to do it in a way that's platform- and code-independent, not to mention one that's scalable and flexible.
It would be possible to hammer out Java code or a set of Unix scripts that could manage a series of processessuch as the steps taken by an insurance broker running a series of Web-based applications to match the needs of a customerbut the task would be laborious, and the finished code would likely be cumbersome. Writing a BPEL application, on the other hand, provides a layer of abstraction through which all the steps can be connected and managed.
Sitting in front of a BPEL designer graphical user interface, a business manager such as our insurance broker could define a business process in BPEL that would be independent of the underlying applications. If those applications were to change, the insurance broker's arrangement of them in the BPEL designer GUI could stay the same. Or if the insurance broker's business plan changed, he could rearrange the processes, as well as add new ones or subtract others, within the GUI.
To run BPEL code that has been generated, either through a GUI or by an intrepid XML programmer, the code is parsed by a BPEL engine, which does the same kind of parsing job as other XML interpreters. Each process that's run is characterized by a Web Services Description Language (WSDL) document, and its messages are transmitted across the Web by the Simple Object Access Protocol (SOAP). Processes that look up available Web services can use the Universal Description, Discovery and Integration (UDDI) directory.
In order to define business processes, BPEL has been endowed with a variety of XML constructs, including "partners," which are definitions of the actors in a business transaction; "containers," which are definitions of the messages that need to be transmitted; "operations," which are definitions of the type of Web services that are required; and "port types," which are definitions of the kinds of Web services connections that are required for operations.
BPEL's capacity goes beyond the range of traditional, definitional XML types. By defining processes, it blurs the distinction between XMLa definition languageand executable languages like Java and Unix shell scripts; hence the "execution" in its name.
Additional Resources


White Papers & Webcasts
Extending COBOL to SOA, Web Services and Beyond
Most businesses have come to realize that recycling or reusing proven processes in combination with newer technologies addresses current and future business needs....
Usability Is Everything
Learn what sets Workday's HR and Payroll solutions apart from the competition....
Extend, Replace, or Convert; which is the best way forward for COBOL Applications?
There are a number of choices when looking at ways to take existing COBOL applications forward. This white paper discusses the most common...
The Value of Real SaaS at Workday
Cost savings, speed to value, and innovation brought to the enterprise by Workday's software-as-a-service solutions for HR and Payroll....
Accelerate SSL Encrypted Applications
The amount of SSL traffic is growing in the enterprise. Because it is encrypted, it cannot be properly controlled and accelerated. Blue Coat...
SaaS at Flextronics, Inc.
Dave Smoley, CIO of Flextronics, discusses the real value of software-as-a-service and why he chose Workday for his HR solution....
ESG Lab Field Audit
Many companies have successfully implemented Riverbed WAN optimization solutions within their Cisco networks. This ESG Lab Field Audit document explores the success that...
Why Compliance Pays
This OnDemand webcast explores the relationship that firms with best compliance records have higher revenue, greater customer retention, lower financial losses from data...
Shape Your Apps Strategy to Reflect New SaaS Licensing and Pricing Trends
Why are smart companies choosing software-as-a-service? Find out in the complimentary Forrester Research report...
Agile Enterprise Content Management (ECM) for Rapid ROI
Find out how combining ECM and BPM will help adress issues about content rich business processes....
Subscribe to Computerworld
