Will BPEL and WSCI Come Together?

By Thor Olavsrud

(Back to article)

A potential rift between the supporters of two specifications, which both address what is considered by many to be a fundamental component of the next level of Web services, may be averted.

At the first meeting of the OASIS Web Services Business Process Execution Language (BPEL) Technical Committee last week, the committee agreed to accept the invitation of the chairs of the World Wide Web Consortium Web Services Choreography Working Group to attend that group's next face-to-face meeting and "explore possible liaisons," according to OASIS spokesperson Carol Geyer. The meeting will be held June 18-20.

The meeting may not only imply a thawing of relations between the various companies involved, but may also signify an end to any potential rivalry between the OASIS and World Wide Web Consortium (W3C) standards bodies.

BPEL -- co-developed by BEA Systems, IBM, Microsoft, SAP and Siebel Systems -- provides a language for the formal specification of business processes and business interaction protocols. By doing so, it seeks to give Web services the ability to support business transactions. The specification defines an interoperable integration model intended to facilitate the expansion of automated process integration in both the intra-corporate and the business-to-business spaces. The complementary specifications WS-Coordination and WS-Transaction orchestrate the choreography of Web services while BPEL serves to articulate them.

The Web Services Choreography Interface (WSCI) specification -- co-developed by BEA Systems, Intalio, SAP, and Sun Microsystems is an XML-based interface description language that describes the flow of messages exchanged by Web services in choreographed interactions. It seeks to describe the observable behavior of Web services in terms of dependencies among exchanged messages, featuring sequencing rules, correlation, exception handling and transactions.

The acceptance of a meeting between the groups working on the two specifications may be a further sign of a willingness to join forces on defining standard methods for business process execution and choreography between Web services. While the two specifications share two developers in common (as well as a number of Working Group/Technical Committee members), they had become the focus of a battle between four Web services giants over the future of that technology, with IBM and Microsoft lining up behind their creation, BPEL, and Sun Microsystems and Oracle throwing their weight behind the WSCI specification.

And the Winner is BPEL?
Analysts and vendors broadly agree that BPEL is the likely winner of a confrontation between the two specifications, noting that the combination of IBM, Microsoft, and a mature specification makes it an 800 lbs. gorilla.

"It looks like BPEL is going to win," James Philips, vice president of products and marketing for Web services management specialist Actional, told internetnews.com. "It's almost a de facto win."

He added that Actional has decided to commit to BPEL, even though OASIS is only now beginning to hammer out a recommendation on the specification. "At the end of the day, it all comes down to a business decision," he said. "It's where the wind is blowing. Basically, we want to support our customers. You've got IBM, BEA and Microsoft all throwing their weight behind BPEL -- that's greater than 90 percent of the application server marketplace right there."

Oak Grove Systems, which focuses on selling business process execution technology and which is also one of the members of the Business Process Management Initiative (one of the creators of WSCI as well as the Business Process Management Language), feels the same way.

While Chuck Ames, CEO of Oak Grove, says that the company takes a neutral approach with its Reactor 5 business process management engine, he noted, "I think we can all see the writing on the wall. When IBM and Microsoft throw their weight behind it, that's the gorilla approach."

He added, "The industry momentum is certainly behind BPEL right now. WSCI and some of the [other specifications] are actually not duplicates of each other. I think BPEL has already established mindshare that is insurmountable, so these others may not matter much in the future."

BPMI.org has acknowledged the similarities between its BPML specification and BPEL, and has moved toward embracing BPEL.

Initial Rift
But while the industry consensus seems to support BPEL, there is considerable commercial advantage in getting in at the ground floor of the development of a new specification in order to be sure that it answers the demands of customers. One of the first signs that the firms would use BPEL and WSCI as a battleground, and one which cast a potential pall on the future of Web services, was Microsoft's abrupt decision in March to pull out of the WSCI Working Group after only one meeting.

At the time, Stephen O'Grady, a senior analyst with research firm Redmonk, said, "I saw that move, and I must say that it doesn't bode well for the future of Web services. I was just chatting with [group marketing manager for Web services standards and technologies at Sun] Ed Julson and a few others from Sun about the state of Web services last week, and while I wasn't entirely convinced then with their pessimistic outlook, this is certainly another step in that direction."

But in a sign that the future of Web services might not be that dire after all, WSCI heavy-weights Sun and Oracle seemed to extend the olive branch earlier this month when they announced they would join the BPEL Technical Committee.

"There's nothing at all surprising about Sun's changing their mind, as their software strategy has been rudderless for over a year now. When you put this week's change of direction in the context of all the zigzags Sun has been making since Web Services got off the ground, it might look like Sun is desperate -- and maybe they are," said ZapThink Senior Analyst Jason Bloomberg.

Redmonk Senior Analyst James Governor agreed the development was not a surprise. "One reason to be on these bodies is so you don't miss the boat. Sun obviously can't really afford not to know what is happening with its competitors' business process management approaches," he said.

A Thawing of Relations
But the parties' decision to explore liaisons seems to indicate a more thorough thawing of relations, answering the often-stated plea of multiple vendors in the space. "We'd like to see it resolved," Actional's Philips said. "We'd like to see systems in the marketplace embodying these standards as rapidly as possible."

That may be just what is taking place, according to ZapThink Senior Analyst Ronald Schmelzer. "They're trying to establish some real connection between the two," he said. "It's at least a sign that there's an interest in talking. It's really about extending the footprint of BPEL."

Forrester Research Analyst Ted Schadler agreed. "What they're doing now is building bridges," he said. "This is an example of that bridge."

Noting that he sees WSCI disappearing in favor of BPEL, he said of Sun's and Oracle's apparent decision to join forces with Microsoft and IBM, "That's what should happen. That's called taking the high ground."

The rest of the BPEL Technical Committee's initial meeting primarily dealt with administrative details of starting up the committee -- especially the difficulties holding meetings through conference calls with more than 100 participants. OASIS' Geyer said 115 OASIS members participated in the first call.