Two camps have emerged in recent months in the area of web services choreography, which is otherwise known as workflow or orchestration. One is the Web Services Business Process Execution Language (WSBPEL) camp, developed by IBM Corp and Microsoft Corp initially but since handed to the OASIS standards body for ratification. The other is the Web Services Choreography Interface (WSCI) specification, developed by Sun Microsystems Inc with Oracle Corp’s backing and then handed to the World Wide Web Consortium (W3C) standards group.

Numerous vendors support both standards efforts, including Sun and Oracle, as well as BEA Systems, EDS, Intalio, Novell, SAP, SeeBeyond Technology and Tibco Software.

Earlier this week, ComputerWire reported that members of the OASIS WSBPEL technical committee agreed last Friday to attend the next meeting of the rival W3C working group, next month. That appeared to open the door for work on interoperability between the two standards.

But late Wednesday in an interview with ComputerWire, IBM’s Bob Sutor, director of WebSphere Infrastructure Software and a key thinker when it comes to IBM’s standards efforts, said that the chances of IBM lining up behind the W3C’s Web Services Choreography Interface (WSCI) standard are remote. We probably won’t, he said.

Sutor, who used to be chief of strategy at OASIS, as well as a participant in numerous W3C standards efforts, said: We have always felt that WSCI was really very tiny compared to BPEL. BPEL is relatively complete, and based on very strong program constructs. But the biggest thing is that [BPEL] ties in well with transactional systems.

When you do these transactional systems you need to be able to say, ‘do A, B and then C’, he said, but you get to a point where WSCI doesn’t do that, it doesn’t handle transactions. It doesn’t have the execution you get with business process execution language.

Nevertheless, would it not make sense for IBM to work with the W3C regardless, and take the best parts of each scheme to create a single standard? Not according to Sutor. You can do everything with BPEL that WSCI can do, and more, he said.

Sutor also argued that observers who suggested BPEL should have been submitted to the W3C instead of OASIS, are missing the point. It’s not like the W3C was the first standards body in the space, in fact before them there was the IETF [Internet Engineering Task Force]. IBM is a member of 300 standards organizations. We have more members at W3C than anyone else, he said. You decide who it is best to work with on a particular project, and who your partners want to work with, and make your choice. You don’t do that based on whose feelings you might hurt. In this case, the only reason to go to meet W3C would be for PR, to show everyone that it’s one nice big family.

W3C WS-Choreography co-chairs Martin Chapman and Steve Ross-Talbot issued the invitation last month, following growing discord around the subject of the choreography of web services. Interestingly, Steve Ross-Talbot also happens to be one of the BPEL Technical Committee’s liaison officers, coordinating the BPEL’s liaisons with other groups. Ross-Talbot is founder and chairman of SpiritSoft Ltd.

At the May 16 OASIS WSBPEL meeting, it was unanimously agreed that representatives should attend the forthcoming W3C meeting. Yet if Sutor is right, their attendance at that meeting may still not mean that a single standard for web services choreography is any closer.

With major vendors pursuing two different standards, Oracle and others have warned of web services fragmentation as companies may implement different specifications in their products. Having two different standards for web services choreography could impede the progress of web services, because it could mean that two or more web services implemented according to different standards would lack interoperability.

Source: Computerwire