RealTime IT News

Oracle, Sun Offer Messaging Spec to W3C

A consortium of IT companies has put its weight behind a new specification it hopes will improve the way messages are sent between Web services platforms.

The WS-MessageDelivery specification 1.0 has been submitted to the World Wide Web Consortium (W3C), which will now consider giving it a stamp of approval.

A bevy of companies including Oracle, Sun Microsystems, Hitachi, Nokia, Arjuna Technologies, Enigmatec Corporation, IONA Technologies, SeeBeyond, and Sonic Software helped author the specification.

The group suggested the API set will make it easier to build complex applications using Web services because it standardizes the way Web service endpoints are referenced when multiple Web services used in common exchange patterns.

The bid is similar to the WS-Addressing proposal submitted by BEA, IBM, and Microsoft . Without officially giving its endorsement, however, a W3C staff comment suggests WS-MessageDelivery may win out in the end.

"While addressing the same scope as the WS-Addressing document, WS-MessageDelivery is more fully integrated with WSDL, by defining its relations with the WSDL Message Exchange Patterns or by introducing a WSMD description for WSDL," the W3C said in its report.

The W3C was also pleased that WS-MessageDelivery follows the current work of the W3C Web Services Description Working Group, and the service references introduced in Web Services Description Language (WSDL) 2.0.

"WS-Addressing, while relying on the WSDL concepts, does not use the WSDL service element as a service reference. WS-MessageDelivery relies on the implicit open content model of WSDL for extensions, while WS-Addressing uses an explicit extension mechanism (the reference properties)," the staff said in its report.

"We're making a level playing field for messaging," Joe Keller, Sun vice president Java Development Platforms, told internetnews.com. "You already have this type of capability in an operating system. What this specification does is extend Web services messaging to all systems."

For example, the message exchange pattern enabled by WS-MessageDelivery is the "callback pattern," where one service sends a request to a second service, but instead of waiting idly for a reply, continues doing other work until notified that the second service has finished processing the request. Prior to WS-MessageDelivery, messages would have to depend on proprietary messaging structures, which limited how vendors were able to interoperate and develop their products.

Keller said the group is welcoming additional contributions of Web services specifications to open standards processes.

The W3 staff is recommending that work on WS-MessageDelivery should be developed in a separate working group from those developing XMLP, WSD, or WS Choreography.