The World Wide Web Consortium has created a new working group to develop an XML-based messaging protocol, but the international standards body says it won't rubberstamp Microsoft's Simple Object Access Protocol - SOAP - as some vendors had hoped.

W3C's XML Protocol Working Group will develop a common way for Web applications to communicate with each other in an automated fashion using XML-encoded messages. An anticipated feature of the next-generation Web, XML is a simple, flexible text-format designed for large-scale electronic publishing.

Vital Having an XML-based messaging protocol is considered critical for the development of business-to-business Internet applications. For example, it would enable a company's Web site to get a real-time stock quote from a financial Web site without the two Web sites sharing the same operating system, application software or programming language. This type of server-to-server communication would be useful for validating credit cards used in online purchasing and checking a manufacturer's inventory for a product sold by a reseller.

Microsoft is pushing SOAP as the solution to this Internet communications problem. Last May, a group of 11 companies including Microsoft, IBM, Compaq and Hewlett-Packard submitted Version 1.1 of SOAP to the W3C for consideration as a standards-track document.

SOAP on the ropes Instead of creating a SOAP working group, the W3C broadened the scope of the effort. The W3C established an XML Protocol Activity as an umbrella group, and under that activity it chartered one working group to develop a simple XML-based messaging format. Other XML-protocol development efforts in such areas as security may be added later.

"This is not an attempt to standardize SOAP," says David Fallside, leader of the W3C working group and a senior technical staff member at IBM for XML standards and strategy. She adds: "The group is going to create a requirements document to detail the points that we feel strongly about. We'll look at SOAP 1.1 as a potential solution, but if we think we can come up with a better way, we will."

UN Fallside says the XML Protocol Working Group will co-ordinate its efforts with the Internet Engineering Task Force, which oversees transport mechanisms such as HTTP, and ebXML, and is developing e-commerce standards for the United Nations.

"There's a lot of interest in XML remote procedure calls such as SOAP," Fallside says. "The Web community needs a fairly simple way of enabling peer-to-peer Web applications to communicate. Right now, communication is primarily between Web browsers and Web servers."

First time The XML Protocol Working Group will host its first face-to-face meeting in October, with an initial working draft of the protocol due next January.

One unusual aspect of the XML Protocol Working Group is that it will conduct all of its business in public, W3C spokeswoman Janet Daly says. The working group's charter, members and meeting minutes will be posted on the W3C's Web site.

Daly says: "Any curious developer can watch what the group is doing."

Traditionally, the W3C provides its documentation to members only, while other international standards bodies such as the IETF conduct their business on public mailing lists.