Web Services Description Language (WSDL) 1.1 now in the Hands of W3C

SAN JOSE, CA—The cause of open standards moves forward apace. The latest development: The W3C has accepted the submission of the 1.1 release of the Web Services Description Language (WSDL) specification for standardization. The submission by WSDL co-authors IBM and Microsoft, along with 23 other companies, represents the highest number of co-submitters ever on a specification contributed to the W3C. Among the companies endorsing the WSDL submission were Ariba, Hewlett-Packard, Oracle, Intel and Commerce One. The previous record was 11 co-submitters of the Simple Object Access Protocol (SOAP), also co-authored by Big Blue and MS.

WSDL is an XML-based language used to describe programs accessible via the Internet (or other networks), and the message formats and protocols used to communicate with them. WSDL is important because it enables Web services to describe their capabilities in a standard way, which allows for easier interoperability among Web services and development tools.

"We spent the 90s working out the standards for Web documents, things like HTML," said Bob Sutor, IBM's program director for e-business standards strategy in Somers, NY. "What we need now is a similar stack of standards for the way we use the Web for business. And that boils down to open standards. It's got to be about interoperability."

According to Sutor, WSDL complements the UDDI (Universal Description, Discovery and Integration) registry, the cross-industry initiative designed to accelerate and broaden business-to-business integration and commerce on the Internet. The UDDI initiative was intended to form a collection of registries and databases describing what businesses do and how to access their services electronically.

"WSDL gives us a good start toward helping people to describe their services in a standard way," Sutor said. "UDDI helps people to publish [those services]."

WSDL was developed outside of the UDDI group and will either formally be submitted to the coalition for a specification or be submitted to a separate standards organization. Sutor said WSDL would not be the only choice for describing Web services. Microsoft and IBM felt it made sense to combine their efforts, he said. "This is a straightforward merger of the two approaches," Sutor said. "They were very close to begin with."

IBM is sponsoring a W3C workshop, scheduled for April, focusing on Web services descriptions, security, reliability, and workflow. Co-chaired by David Fallside, IBM's senior technical staff member for XML standards development and head of the W3C's XML Protocol working group, the workshop's mission is to facilitate discussion on what new standards activities in the Web services area should be started and how to best implement these working groups quickly and efficiently.

After the workshop, the W3C is likely to set up several working groups relating to Web services, Sutor said. It is within its working groups that the W3C develops its specifications. In this case, the working groups would be starting with a fairly advanced version of WSDL, but the process is bound to change it. The W3C established the XML Protocol Working Group in response to last year's IBM/Microsoft SOAP submission.

The WSDL specification is currently available on IBM's developerWorks Web site and Microsoft's site. IBM, although fully supporting the open standards approach, was never one to wait around for the specs to arrive fully cooked. The company is offering developers the WSDL Toolkit, the Web Services Toolkit, the Web Services Development Environment, and other tools for SOAP and UDDI, all available from its alphaWorks Web site.

About the Author

John K. Waters is a freelance writer based in Silicon Valley. He can be reached at [email protected].