On August 1, 2001, the World Wide Web Consortium released a public draft of SOAP v 1.2 designed to define messaging formats between different architectures. It removes ambiguities on how messages are processed, provides more feedback in error messaging, and updates the XML Schema and name spacing.
In September 2000, the OMG’s Platform Technology Committee (PTC) began work on a standard meant to integrate SOAP with OMG’s CORBA. It allows SOAP clients to invoke CORBA servers, and CORBA clients and servers to interoperate using SOAP. The PTC also looked at efforts to standardize methods to transmit CORBA network packets through firewalls and to adapt real-time object request brokers to emit alternative protocols needed for telecommunications and other real-time applications.
The SOAP was born out of an idea for an XML-based RPC mechanism originally fostered by Dave Winer of Userland Software back in 1998. The idea evolved through a joint effort of Winer, Don Box at DevelopMentor, and Microsoft to publicly emerge as SOAP version 0.9 in the latter part of 1999. At that time, the reaction of the developer community was mixed.
IBM officially joined the SOAP development effort in May of 2000 by co-authoring the SOAP version 1.1 specification, co-submitting it as a W3C Note, officially signaling the start of the “Web services revolution.” With IBM on board, developers on non-Microsoft development platforms stood up and took notice of SOAP for pretty much the first time.
From that point on, Microsoft and IBM took the lead in putting SOAP-enabled development tools into the hands of developers. Starting simple, IBM was the first to produce a Java-based toolkit for SOAP that was donated to the open-source Apache Software Foundation for further development. Microsoft released the first rendition of its SOAP Toolkit soon thereafter and announced their massive .NET Web services initiative the following July.
With industry support for SOAP growing rapidly, IBM and Microsoft next turned their attention to filling the various holes in the Web Services Architecture that was emerging. Namely, with the potential that SOAP-enabled applications would grow rapidly, there needed to be a mechanism for describing the capabilities of such services as well as a mechanism for locating services once they had been deployed. In September 2000, Microsoft, IBM, and Ariba jointly announced the UDDI. Then, just a matter of weeks later, the same three companies announced the WSDL, an XML grammar for describing the capabilities and technical details of SOAP-based Web services that compliments SOAP by allowing for dynamic cross-platform integration.
There are at least 39 different implementations of the SOAP Specification, with growing support for multiple operating systems and development languages. While each of these has its own level of capability, standards support, and quality control, they all share at least one thing in common: they all understand how to create and consume SOAP Envelopes. Regardless of how the tool was implemented, or where it is deployed, there exists the potential of seamless interoperability that would allow applications written in one language on one platform to consume the services of applications written in a completely different language on a completely different platform.