Organizations that attempt to do business online quickly learn that there are lots of IT-related problems that others have already solved. Increasingly, those solutions are becoming readily available to anyone, in the form of Web services. Web services are perhaps the latest, most powerful example of reusable program components, the difference being that instead of incorporating component code directly into your application, you simply access the service over the Web, pass your parameters along to it and let the remote service do the work for you.
It's an extraordinarily powerful model, but with one major hitch: How do you find out what Web services are available, where they are and how you use them? Businesses need to be easily able to discover one another, make their needs and capabilities known and integrate services using each business's preferred technology, Web services and commerce processes.
Until recently, there was no simple way to get information about businesses and what services they support and no single point of access to obtain that information. Now there is Universal Description, Discovery and Integration (UDDI), a standards-based system for registering Web services.
UDDI is an industry effort started in mid-2000 by Ariba Inc., IBM and Microsoft Corp., along with 33 other companies. Today, UDDI has more than 300 community members, including American Express Co., SAP AG and Ford Motor Co. The UDDI group doesn't call itself a standards body, even though it offers a framework for integrating Web services. The UDDI specification utilizes World Wide Web Consortium and Internet Engineering Task Force standards such as XML, Simple Object Access Protocol (SOAP), HTTP and Domain Name System protocols.
UDDI entered its public beta-testing phase in November 2000, when the three founding members each set up a registry server compliant with Version 1.0 of the spec that would interoperate with other members' servers. As of mid-2002, all publicly available nodes of the UDDI Business Registry (UBR) have been upgraded to Version 2.0.
On July 30, technical development and management of the UDDI project was transferred to Santa Clara, Calif.-based Organization for the Advancement of Structured Information Standards, a global consortium developing and promoting e-business standards.
How UDDI Works
At its heart, UDDI is a database that's searchable by type of business (typically identified using the North American Industry Classification System-NAICS-or the Standard Industrial Classification), business name or geographical location.
Let's say you have an electronic order-entry system that relies on SOAP-based Web services and you want to do online business with computer makers. You'll first need to know which computer makers have compatible Web services. A search of UDDI would return a list of those computer companies that have registered with the system.
UDDI registration is open to companies worldwide. When a business registers with UDDI, it provides the registry with "white pages" information about itself (including items such as name and contact info), "yellow pages" taxonomies (including NAICS business identifiers, products, services and geographic location) and "green pages" information describing the company's business processes and how to do business with it.
Each service listed in the UDDI registry is identified as being a specific type of service with a unique identifier that comes from a pool of well-known service types already registered with UDDI. Service types registration includes a pointer to the namespace containing the service type description, who published the service, and a service type registration identifier, called a tModelKey.
While the registering business provides most registry information, the service type is normally entered by software developers, standards bodies or programmers.
UDDI doesn't dictate that an organization must use a specific technology or methodology to describe its Web service interface. A company is free to use simple prose, more formal description languages, an XML schema or Web Services Description Language.
More than 10,000 businesses have registered with the three public UBR nodes, along with 4,000 individual providers of Web services. All registered data is replicated among all the UBR nodes.
Currently, there are three UBRs, with a fourth from Tokyo-based NTT Communications Corp. due to come online this fall. Hewlett-Packard Co. was operating a UDDI registry but in July announced that it would discontinue hosting the node. HP did say, however, that it intends to continue to support UDDI.