DETROIT - Seeking to reconcile two rival XML standardization efforts while avoiding the costly and complicated process of supporting incompatible systems, General Motors, Ford Motor Company and DaimlerChrysler last week together endorsed a plan calling for the auto industry to use a single XML-based data exchange of business documents.The format-neutral XML is widely seen as a more flexible method to define sharing business content than electronic data interchange (EDI), the method the auto industry has used since the 1980s. The Big Three automakers and several of their suppliers last week said it makes sense to re-tool for XML. However, the World Wide Web Consortium (W3C), which offers\u00a0Web services, and the Organization for Advancement of Structured Information Standards (OASIS), with its e-business XML (ebXML) plan, present two similar but competing approaches."Both [W3C and OASIS] leverage XML but are largely incompatible," said John Jackson, GM's director of enterprise software, during his presentation at the annual Auto-Tech conference organized by the Automotive Industry Action Group (AIAG). The AIAG is the trade organization that for two decades has brought together the Big Three and their suppliers to hammer out IT issues.The answer for now, the Big Three say, is they are going to use their collective clout to push W3C and OASIS for convergence on XML standards. Because if that fails, the industry faces an increased risk of interoperability problems and a lower adoption rate for XML, they say."If I'm doing ebXML and my partner is doing Web Services, it's not going to work," said Tim Baeten, who leads the technical group at Ford designing the automaker's next-generation interoperability platform. Baeten is also co-chair of the AIAG's B2B Convergence Work Group."Convergence" suggests that the W3C and OASIS would agree on a common messaging approach, which is one way Web services and ebXML differ. There's some optimism that demands from the Big Three might help that happen - but perhaps not fast enough for the auto industry."I expect convergence, but I don't think it will occur in a reasonable time frame," Jackson said.Ford already uses Web services to share data with suppliers through its e-Hub portal, while GM and Volkswagen have placed their bets on Web ebXML. Suppliers to the Big Three say they're concerned that if the XML standards issue isn't sorted out early, they will face demands from the automakers to use incompatible products. This issue is a cost and operational burden for parts manufacturers, despite the shift from proprietary networks to the Internet and use of some shared e-commerce facilities such as the Covisint Web portal."We're concerned that we don't end up with requirements from customers to do multiple things [with XML]," said Gene Hopkins, director of business-to-business communications at ArvinMeritor, a truck and trailer parts manufacturer in Troy, Mich.The Big Three carmakers and suppliers last week made it clear they aren't going to sit around waiting for that hoped-for convergence to happen.Under the auspices of the AIAG, the carmakers this month finished their own XML-defined business documents for auto industry inventory management. They expect to define more business documents by year-end and submit them to OASIS and W3C for review.They also want software vendors to implement their XML-defined business documents in products. "One thing we learned a year ago is that standards groups and vendors want specific requirements from us," Baeten said.With the prospect of the auto industry designing a new model of data sharing, Microsoft this year joined the AIAG, sponsoring the Auto-Tech conference breakfast and adding its name to the conference badge-holder."We want to help drive this sort of initiative," said John Stenlake, architect at Microsoft consulting services, who spoke during a panel discussion at the conference. Stenlake joined the company earlier this year from Ford, where he was chief software architect. He noted that automakers now see Microsoft as the "800-pound gorilla" at the AIAG on the XML question.Stenlake said Microsoft is advocating Web services for the auto industry - as is IBM, according to Rob Cutlip, solutions\/software architect in the IBM Software Group, Solutions and Strategy Division. Both computer architects spoke during the panel discussion."We're not trying to create an abstract layer by committee,"Cutlip said. "That doesn't succeed." Though both hope to see convergence, Cutlip said,the reality is that a lot more investment is going into Web Services than ebXML.Although the AIAG a few years ago expressed official support for ebXML as it was ramping up, the wind seems to be shifting toward Web services if only because AIAG members such as IBM and Microsoft say that's where they are putting their bets.The bottom line, according to the carmakers striving to work for industry interoperability, is that manufacturers need to be able to buy e-business software that works for the purposes of sharing XML data based on an agreed-upon business model. They want it to be based on standards, but in the end what counts is what works."You don't buy from the standards bodies," GM's Jackson noted. "You buy from the likes of Microsoft and IBM."