Microsoft, IBM Reveal New Spec. for Discovering Web Services
- By Matt Migliore
continues to develop specialty standards on top of the base Web services stack, teaming with IBM Corp.
to propose a specification for Inspection after announcing specs for licensing, routing and security last month at its Professional Developer Conference.
The spec., called WS-Inspection, is designed to allow an application to interface with a Web site in order to find out what Web services a particular organization offers. Microsoft and IBM are touting WS-Inspection as complementary to Universal Description, Discovery and Integration, a global directory for listing Web services that IBM and Microsoft have been promoting heavily for the past year.
Philip DesAutels, product manager of the XML Web Services group at Microsoft, says while Web Services Description Language allows developers to describe a specific service, and UDDI serves as a Yellow Pages for Web services, “what we don’t have between [WSDL and UDDI] is a way to go in and talk to the server.” According to DesAutels, WS-Inspection solves this problem.
Essentially, WS-Inspection is a public protocol for communicating with proxy servers, says DesAutels. He says it is based on the internal proxy-server protocols used by both Microsoft (DISCO) and IBM (ADS). “We took the best of both DISCO and ADS [to build WS-Inspection],” says DesAutels.
The key difference in how Microsoft and IBM are positioning WS-Inspection and UDDI lies in how the two technologies are used. Microsoft and IBM believe WS-Inspection is a better solution for organizations with existing relationships to discover each other’s Web services. UDDI, on the other hand, is viewed in the mold of a traditional Yellow Pages directory that organizations can use to get a series of listings for Web services under different categories.
Nevertheless, WS-Inspection does seem to have some overlap with UDDI. If WS-Inspection and UDDI are both adopted on a widespread scale, organizations in search of Web services will have two ways of finding them.
Many opponents of UDDI argue that it is unreasonable to believe enterprises will use UDDI to create business relationships based simply on a listing in a registry. In a recent conversation with Web Services Report, Mike Gilpin, vice president and research leader for Gaga Information Group, said of UDDI in an enterprise environment, “Nobody’s going to wake up and go ‘Gee, I wonder where I’ll buy stuff from today.”
At this point, Microsoft and IBM say WS-Inspection will allow developers to discover services that aren’t listed in UDDI registries. However, if doubts about UDDI like that which Gilpin and others have expressed continue to grow, WS-Inspection could emerge as an alternative.
WS-Inspection builds on the Simple Object Access Protocol discovery technology Microsoft’s Visual Studio .NET, which is slated for release by year end. WS-Inspection implementations are also available with the latest version of the IBM Web Services Toolkit 2.4.1. Both IBM and Microsoft are optimistic other industry leaders will soon declare support for WS-Inspection (Oracle, Sun Microsystems and BEA Systems have already announced support for the WS-Licensing, WS-Routing and WS-Security.). ###
For more information about WS-Inspection, visit www-106.ibm.com/developerworks/library/ws-wsilover/index.html.
Matt Migliore is regular contributor to ENTmag.com. He focuses particularly on Microsoft .NET and other Web services technologies. Matt was the editor of several technology-related Web publications and electronic newsletters, including Web Services Report, ASP insights and MIDRANGE Systems.