W3C Issues Key Web Services Standards

The World Wide Web Consortium (W3C) has published three new standards to help vendors such as Microsoft, IBM and BEA Systems improve Web services performance for customers.

The standards body on Tuesday issued XML-binary Optimized Packaging, SOAP Message Transmission Optimization Mechanism and Resource Representation SOAP Header Block to help developers package and send binary data in a SOAP 1.2 message.

The new schemas aim to solve a much-maligned problem in sharing and employing data between different flavors of Web services software. This includes simple tasks such as sending a video clip from a handheld computer to a desktop and major jobs such as exchanging large documents among several collaborators.

A major part of the problem is that Web services applications are based on XML . This is a sufficient language for simple reading tasks. But when a programmer encodes binary data as XML, it yields a large, or "fat" file that sops up bandwidth and slows down applications.

When users try to run this software on computing devices, performance is so slow that it often renders tasks unmanageable. The new standards should ease some pains, said Yves Lafon, team contact for the group tasked with optimizing XML for Web services, the XML Protocol Working Group.

Lafon told internetnews.com the XML-binary Optimized Packaging (XOP) and the Message Transmission Optimization Mechanism (MTOM) provide a more efficient way to transmit a SOAP message. XOP includes binary data along with and XML document in a package. MTOM uses XOP to let SOAP bindings speed up data transmission, he said.

This, Lafon said, makes Web services faster and more usable. But the process was hardly easy. Lafon said his group started with a single specification for optimizing XML that employed XOP and MTOM.

Realizing that one spec was not enough to encode binary data in XML, the group developed the Resource Representation SOAP Header Block (RRSHB) parcel to send all the data needed to process the message -- even when the data would not be quickly available due to slow bandwidth or lack of file access.

However, Lafon warned that XOP is not a comprehensive resolution for the problem of putting binary data in XML, noting that the W3C XML Binary Characterization Working Group is looking at different ways to process binary data in XML.

Zapthink analyst Ronald Schmelzer said the idea of making XML more efficient is becoming more popular, noting that businesses will ramp up the amount of XML they employ in their networks, expanding from 15 percent today to almost 50 percent by 2008.

Schmelzer said the fact that XOP aims to allow XML to support large binary media types is an indication of the prevalence in which XML is being used for new applications that are outside the bounds originally conceived of for the language. MTOM and RRSHB, Schmelzer told internetnews.com, will boost efficiency by trimming the traffic that SOAP messages can create.

IBM , Microsoft and BEA expressed support for the new Web services standards in a statement. The three companies are pacing the industry both in Web services products and standards but have not found an answer to the XML optimization issue.

The progress should also benefit vendors such as DataPower, Tarari and Rogue Wave, which are working to boost the performance of XML and Web services.