The Web Service Description Language

IBM and Microsoft have jointly published the Web Services Description Language (WSDL) specification. The new specification closes a technical split that could have impeded the development of Web services, which both companies are promoting as a solution for business-to-business (B2B) application integration. WSDL could also work together with the UDDI (Universal Description, Discovery, and Integration) registry to automate parts of B2B integration process.

As its name implies, WSDL is a language for describing Web services. A Web service is a software component (similar to a COM component or software library) that allows applications to invoke its functions by sending it messages over standard Internet protocols. When used for B2B integration, Web services act as gateways to applications (e.g., Enterprise Resource Planning systems) running at separate companies and receive messages carrying business documents (such as purchase orders, requests for quotes, or invoices). For example, a billing application might call a “submit invoice” function of a customer’s Web service to send an electronic invoice to the customer’s payables application.