A standards body working on protocols for Web services has begun crafting a specification for reliability that will help plug a hole in the budding technology that is stifling enterprise adoption.
The Organization for the Advancement of Structured Information Standards (OASIS) on Wednesday said it is forming a Web Services Reliable Messaging (WS-RM) technical committee that will develop a specification to guarantee the delivery of messages between applications, especially those executing business transactions.
Reliability and security are two areas of Web services development that corporate users are closely watching. Both are needed to ensure that Web services can live up to enterprise demands for distributed computing.
WS-RM will work with Simple Object Access Protocol (SOAP), the standard messaging protocol used for Web services. WS-RM information would be inserted into the headers of SOAP messages.
WS-RM will be crafted from the WS-Reliability specification drafted in early January by Fujitsu Ltd., Hitachi Ltd., Oracle Corp., NEC Corp., Sonic Software Corp. and Sun Microsystems Inc. Tom Rutt, IT standards manager for Fujitsu, will serve as chair of the committee.
“For a lot of important applications this sort of reliability can go a long way,” says Rutt. He says applications such as those that do financial transactions must have guaranteed delivery to meet quality-of-service standards. For instance, a message requesting a money withdrawal should be received by an application once and only once.
“We are talking about reliability in a straightforward fashion – a specification without a whole lot of complicated protocols,” says Rutt.
WS-RM will include three types of delivery: guaranteed delivery, which means the message is delivered at least once; duplication elimination, which ensures the message is delivered at most once; and message delivery sequencing, which determines the order in which messages are delivered.
Eventually, the specification will be integrated with Web Services Description Language (WSDL), which is used to describe how a Web service operates and would signal that an application has a reliable delivery capability.
Besides the original companies that drafted the foundation specification in January, the WS-RM technical committee also includes Commerce One Inc., Cyclone Commerce Inc., IONA Technologies PLC, SAP AG, SeeBeyond Technology Corp., webMethods Inc. and WRQ Inc.
Not part of the group, however, is BEA Systems Inc., which is preparing to release a proprietary reliable messaging technology for Web services as part of an upgrade to its WebLogic Platform.
Also missing initially are powerhouses IBM Corp. and Microsoft Corp., which have been major players in crafting Web services standards. IBM has created a similar reliable messaging specification called HTTP-Reliable. HTTP is the transport mechanism for SOAP, and the IBM specification enhances HTTP to ensure that a sender is returned a response of “undeliverable” if their message did not reach its destination.
While the IBM specification is bound to HTTP, the WS-RM proposal allows for the use of any transport mechanism that can be bound to SOAP.
“We have asked these companies to participate, and other submissions of specifications for reliability will be accepted without prejudice,” says Rutt.
Steve Holbrook, program director of IBM’s emerging e-business standards, says the company plans to be an active participant. “While IBM is not joining the effort at the beginning, we are confident that the industry will unite around a common standard. IBM was influential in many of the constructs of WS-RM based on our early work on ebXML,” says Holbrook.
The proposed WS-RM specification incorporates many of the concepts of ebXML’s Messaging Servers specification. The ebXML specification, which was also developed by OASIS, is a set of definitions for electronic transactions and business collaboration.
The WS-RM work will dovetail with other Web services standard work, including OASIS groups working on Web Services-Security and Security Assertion Markup Language, which was recently approved as a standard.
The WS-RM committee plans to take input from the World Wide Web Consortium’s Web Services Architecture Working Group.
The WS-RM technical committee will hold its first meeting by phone on March 26.
A standard OASIS requirements document is expected within two months, with a final draft planned for late September.
