Soap promises clean integration

Details of a technology that allows application developers to exchange both data and processes between Microsoft and...

Details of a technology that allows application developers to exchange both data and processes between Microsoft and non-Microsoft software components have been posted on the Web. Danny Bradbury reports.

The World-Wide Web Consortium has posted a draft specification for Soap - a technology developed by Microsoft to let application developers integrate software components over the Web.

The Simple Object Access Protocol (Soap) service, which was posted early this month, can be used to exchange both data and processes between Microsoft and non-Microsoft systems.

A typical scenario, according to Microsoft staff, is a manufacturer's Soap-enabled system automatically notifying a delivery company's non-Microsoft application that a product is ready to be picked up from the warehouse, thus initiating a delivery run.

Brian Travis, chief technology officer at Architag, a consulting company involved in a Soap roadshow with Microsoft, describes Soap as an envelope for running objects that reside on different machines.

Unlike Microsoft's Distributed Common Object Model (Dcom), which enables Windows code to communicate across different machines, Soap is not dependent on Windows. "Soap is cross-platform, cross-language and cross-object architecture," says Travis.

The submission of the specification to the W3C will interest the Object Management Group (OMG), the standards body that promotes its own object interoperability standard, the Common Object Request Broker Architecture (Corba). Soap will enable developers using any three-tier component-based framework to access components written using other standards. Bill Hoffman, president and chief operating officer of the OMG, greets the news cautiously.

"It is a little too early to tell you whether it is good news or not," he says. "We started out on interoperability with Microsoft in 1994. Unfortunately, Microsoft has never been able to get a good solution for heterogeneous environments. This is a good means for it to achieve that."

Hoffman argues that Microsoft effectively relinquished its bid to make Com+ a heterogeneous system when it bundled its application server, the Microsoft Transaction Server (MTS), as part of its component framework. "It knew it would need some sort of alternative to get heterogeneous functions," he says.

Tony Goodhew, Visual C++ product manager for Microsoft in Redmond, US, is less restrained in his comments about the OMG, commenting specifically on the increasingly close relationship between Corba and Sun Microsystems' Enterprise Java Beans (EJB) standard. "One big problem with the OMG is that it accepted EJB as a Corba 3.0 specification," he complains. "It is a closed propriety language owned by one company."

Microsoft has a history of dancing toe-to-toe with independent standards bodies and suppliers alike in a bid to gain recognition for its proprietary Internet application standards. Its relationship with the OMG really began in 1994 when it offered to try and work with the organisation on a technology bridging Corba and Com. The standard was not ratified until early 1999, after a turbulent process during which the OMG accused Microsoft of providing incomplete standards.

Microsoft subsequently released Com+, an enhancement of the technology with many more services built in.

Goodhew admits that the existing bridging standard between Microsoft and Corba does not support these new services, although Hoffman points out that some OMG member companies have been working with Microsoft to provide Com+ links to their Corba-based development tools.

In 1996 the company shocked the software community by offering its ActiveX technology as an open standard to be governed by the industry. The Open Group - formerly X/Open - took on the administration of the technology, but has maintained a very low profile. The technology is still effectively Microsoft's.

The company also tried to make its Com component framework more interoperable with other architectures by jumping into bed with other suppliers. In late 1997 it worked with Software AG, which released a middleware product called EntireX designed to roll out the distributed Com (Dcom) technology on to multiple platforms. The technology died, not with a bang but with a whimper.

Microsoft's latest move is sure to please developers. And if it makes it to W3C ratification, this achievement will be the company's best hope yet for integrating its component framework with other server-based component infrastructures on its own terms.

Read more on Business applications