The W3C has acknowledged receipt of a submission for version 1.1 of Web Services Description Language (WSDL). The document is signed by more than a dozen companies, and represents a suggestion for describing services for the W3C XML Activity on XML Protocols. Abstract: "WSDL is an XML format for describing network services as a set of endpoints operating on messages containing either document-oriented or procedure-oriented information. The operations and messages are described abstractly, and then bound to a concrete network protocol and message format to define an endpoint. Related concrete endpoints are combined into abstract endpoints (services). WSDL is extensible to allow description of endpoints and their messages regardless of what message formats or network protocols are used to communicate, however, the only bindings described in this document describe how to use WSDL in conjunction with SOAP 1.1, HTTP GET/POST, and MIME." The W3C disposition: "To determine the next steps in the Web Services area, W3C will be holding a Workshop on Web Services. The submitters of WSDL are encouraged to submit a position paper to this Workshop. Moreover, the community is invited to provide feedback on this submission to www-ws@w3.org".

The submission was sent to W3C by the following W3C member companies: International Business Machines Corporation, Microsoft Corporation, Allaire, Ariba, BEA, Bowstreet, Commerce One, Compaq Computer Corporation, DataChannel, Epicentric, Fujitsu Limited, Hewlett-Packard, Intel, IONA Technologies, Jamcracker, Lotus Development Corporation, Oracle, Rogue Wave, SAP, TIBCO, VeriSign, Vitria, webMethods, XML Global Technologies and XMLSolutions.

From the document Introduction:

As communications protocols and message formats are standardized in the web community, it becomes increasingly possible and important to be able to describe the communications in some structured way. WSDL addresses this need by defining an XML grammar for describing network services as collections of communication endpoints capable of exchanging messages. WSDL service definitions provide documentation for distributed systems and serve as a recipe for automating the details involved in applications communication.

A WSDL document defines services as collections of network endpoints, or ports. In WSDL, the abstract definition of endpoints and messages is separated from their concrete network deployment or data format bindings. This allows the reuse of abstract definitions: messages, which are abstract descriptions of the data being exchanged, and port types which are abstract collections of operations. The concrete protocol and data format specifications for a particular port type constitutes a reusable binding. A port is defined by associating a network address with a reusable binding, and a collection of ports define a service.

From the W3C Staff comment on the WSDL Version 1.1 submission [Philipp Hoschka, Architecture Domain Leader]:

Today's Web offers many information- and computing services such as stock quote services, calculators for mortgage payments, or databases for learning details about particular movies. Many of these services are geared towards a human user, i.e. a human fills in input parameters in a Web form, and the results are delivered as part of an HTML file. It is often very useful to reuse these services as part of a computer program that does further processing of the results delivered by the service. However, this is difficult today due to the orientation of the existing services towards a human user. For example, it requires using awkward "screen scraping" approaches in order to extract the results of a query from HTML source code.

The WSDL submission allows building web-based information- and computing-services targeted to computer programs rather than to human users. It allows using an XML-based language to describe Web Services in terms of the type and number of parameters passed to a service, the type and structure of the result returned etc. WSDL also gives example mappings of WSDL descriptions onto a number of Web protocols that can be used for passing parameters and results (SOAP, URL-encoded parameter passing in HTTP and multipart MIME transported via HTTP).