The Universal Description, Discovery and Integration (UDDI) specification is shedding its reputation as simply being the "Yellow Pages" for Web services lookup and discovery. UDDI registries are becoming intelligent repositories that house a plethora of meta data and metrics information around more manageable Web services.
OASIS announced last week the ratification of the UDDI Version 3.0.2, with major updates made to the specification, including support for multi-registry environments, digital signatures and a new subscription application program interface (API), among others.
Version 3.0.2 adds the ability to affiliate multiple registries in an open, standardized way to ensure interoperable communication.
"By allowing you to set keys on your interfaces, you can define what would be called a 'well-known' interface which enables reuse," said Luc Clement of Burlington, Mass..-based Systinet, and co-chair of the OASIS UDDI Specification Technical Committee. "I've defined a schema, I've defined a WSDL and now this information can be propagated from one registry to the other within the enterprise. In v2 that wasn't possible."
Version 3 also continues UDDI's change in focus from simply enabling business-to-business integration toward the enterprise, Clement said.
Another major advancement in the version 3 specification is the support for digital signatures. Inquirers of a registry can now filter their queries, only requesting data that has been signed. Publishers to a registry now have the assurance that they are not being misrepresented by someone claiming to own a UDDI entity, according to OASIS.
"Quality of data was another driver," Clement said. "In earlier versions, you couldn't always validate or authenticate who published a service, so in v3, we've added digital signatures to be able to do that."UDDIs are now being deployed in very diverse environments such as the Internet, extranet, test and production. To facilitate this, a new policy schema and policy guide allow UDDI implementations to support vastly different operational policies, according to OASIS.
"We've added better support for WS-Policy and WS-Policy attachments, which allow you to better represent policies within the registry," Clement said. "In v2, the inquiry APIs were all deemed to be anonymous; this is not a reasonable assumption to make in the context of the enterprise. In v3 we added the ability for every inquiry API to provide authentication information," Clement said.
The new subscription API allows users to track registry activity (even across multiple registries) in both a synchronous and asynchronous manner. Clement believes that this API is integral for the integration of support from vendors of Web services management products.
Other new features in v3 include extended discovery features that combine previous, multi-step queries into a single-step, complex query and the ability to nest sub-queries within a single query, letting clients narrow their searches more efficiently.
Not everybody has jumped on the UDDI bandwagon, however. At the recent Web Services on Wall Street Show & Conference in New York, some speakers adverse to UDDI said work being done around Web services meta data will eliminate the need for such registries.
"Companies that are simply doing point-to-point Web Services (not SOA), might not realize that much benefit from UDDI," said Ron Schmelzer, senior analyst at ZapThink LLC of Waltham, Mass.
"The only real alternatives to a UDDI-based service registry are potentially the ebXML-based registry, and perhaps some proprietary approaches, like the Java-based JavaSpaces or asset or meta data-management repositories," Schmelzer said.
Still, a group of well-known companies are already committed to adopting the new standard, including Systinet, Islandia, N.Y.-based Computer Associates International Inc., Cambridge, Mass.-based DataPower Technology and Germany-based SAP, Clement said. Microsoft is expected to adopt the standard as well, and IBM has a v3 implementation available with WebSphere 6, he added.
"UDDI 3.0 is a step in the right direction," he said. "Companies that are building SOAs are increasingly dependent on service registries to achieve the primary benefit of SOA -- service reuse and composition."
Along with the v3 announcement, OASIS released new technical notes with advice on using UDDI with Web Services Business Process Execution Language, and the process of using JAX-RPC for a UDDI client.
The technical notes represent OASIS' ongoing work to enhance the UDDI specification for future versions. The committee plans on focusing on mapping WS-Security to the specification, adding taxonomy management, providing a better access control model and supporting range and semantic queries, according to Clement.