The new section of the Dot-Com Builder web site features technical overview articles. Anand Rajaram presents an overview of UDDI. Rajaram is an Enterprise JavaTM technology Architect at jPeople and a Sun Certified Java technology Programmer. The article describes the Universal Description, Discovery, and Integration (UDDI) standard which provides a mechanism for businesses to "describe" themselves and the types of services they provide and then register and publish themselves in a UDDI Registry. The capabilities that these registries add to the WWW and how they can be used are also described.

Rajaram discusses where UDDI fits in to the protocols such as HTTP, SMTP, XML, SOAP in the web services Interop Stack. Web services are a new paradigm in distributed systems development that will provide a platform for all future B2B e-commerce transactions on the Internet. eXtensible Markup Language (XML) offers the most promising solution yet for businesses to seamlessly exchange data. Simple Object Access Protocol (SOAP) has also provided an excellent framework for businesses to call each other's services over a network. Businesses published in the UDDI Registry can be searched for, queried, or "discovered" by other businesses using SOAP messages. Businesses can find other businesses to partner with and then "integrate" their services with their partners and provide service to their customers.

A UDDI business registration consists of yellow and white pages similar to a telephone directory and green pages that contain the technical information about services exposed by the business. UDDI registry nodes store the information and replicate the data among them to provide the same directory of information from any of the nodes. This system is similar to how domain names are looked up in the web using the DNS architecture.

The core structures of UDDI are businessEntity, businessService, bindingTemplate, and tModel. The businessEntity structure is used by the business to publish descriptive information about itself and the services it offers. The businessService structure represents the services or business processes provided by the businessEntity. The bindingTemplate presents the important data that describes the technical characteristics of the given service implementation. The tModel represents a technical specification in the form of keyed metadata.

UDDI provides for two broad categories of APIs, the Publish API and the Inquiry API. The Publish API provides the mechanism for service providers to register themselves and their services with the UDDI registry. The Inquiry API allows service subscribers to search for the available services.

Rajaram illustrates UDDI with an example of a courier service that creates a web service that allows their customers to calculate the cost of shipping an item. The courier company could either develop a SOAP wrapper over the existing algorithm that calculates the shipping cost or choose to rewrite it to decipher and deliver SOAP messages. This service could then be published in a UDDI registry. Internet retailers could then use this service to calculate shipping costs for its customers. Rajaram demonstrates how UDDI works with a sample application that invokes a find message using the courier company called ZipZapZoom that has been created in the IBM UDDI test registry for purposes of the article. There are additional technical details, code, and illustrations on the web page.

http://dcb.sun.com/practices/webservices/overviews/overview_uddi.jsp [...read more...]

		fullsource
Print Email Current Profile Archive Blog Generate newsletter