Universal Description, Discovery, and Integration , or UDDI, is the mechanism that provides for the discovery of available web services. The UDDI schema is fairly complex, and I’ll describe it in detail—along with all the other relevant XML schemas—in the following section. In addition to the XML schema, UDDI includes the infrastructure necessary for web service discovery. Access to this infrastructure is itself implemented in the form of web services.

The various UDDI specifications are located at http://www.uddi.org/specification.html. And the major players each have UDDI documentation available on their own web sites; for example, IBM has http://uddi.ibm.com/, and Microsoft has http://uddi.microsoft.com/.