Mark Johnson
Web technologies excel at creating new acronyms. Articles on Web
technology often read like bad personal ads: "XML B2B portal offers end-
to-end EAI solution with ebXML, JMS, UDDI, SOAP...." What does it all
mean? Entire books can (and will) be written about each of these
technologies, so this week, I'll just outline one of new "Web service"
initiative focused on electronic business.
What's a "Web service"? Tim Berners-Lee envisioned the World Wide Web
as simply a collection of hyperlinked, static documents – then along
came dynamic content, server extensions, multimedia, Web-enabled
database products, application servers, and now Web services.
A "Web service" simply performs work on the Web by sending a message to
a Web URL, and usually receiving a reply with some useful information.
Web services require the development of a great deal of infrastructure,
and everybody (well, OK, *almost* everybody) wants open and extensible
Web services. Because of its openness and extensibility, most Web
services work being done today is based on XML.
Using Web services requires a way to (1) find the service, (2) contact
the business, and (3) figure out how to use the service; that's what
UDDI proposes to provide. UDDI (Universal Description, Discovery and
Integration) is a joint effort of Microsoft, IBM, and Ariba to create a
Web-wide directory of Web services. Developers can use UDDI to find
available Web services, and then use those services to create new Web
applications and services.
The UDDI registry contains three types of service descriptions: "white
pages", "yellow pages", and "green pages". White pages are searchable,
human-readable information such as textual service descriptions and
contact information. Yellow pages link business descriptions to
standard business taxonomies, like NAICS (the US Government codes for
industries) and UN/SPSC (the ECMA codes for products and services), as
well as geographical descriptions. Finally, green pages describe online
business processes and services, describe how to access the services
over the Web using standard protocols, and, optionally, categorize the
services.
UDDI hasn't sprung out of nowhere. IBM, Ariba, and Microsoft all have,
not surprisingly, contributed technologies they have developed into the
UDDI specification. Microsoft and IBM collaborated on SOAP (XML Web
service invocation, which I'll in an upcoming newsletter); Microsoft
and Ariba worked together on cXML and BizTalk (cXML is Ariba's
eBusiness XML "language" and BizTalk is Microsoft's messaging
framework, for which they sell a server); and IBM and Ariba have worked
together on B2B initiatives, yet all of the UDDI technologies can be
considered open and standard. Part of the UDDI vision is to license
control and intellectual property to an open, third party standards
body following the technology's third release.
If the UDDI standard succeeds, then UDDI's big-name collaborators all
stand to gain from their head start. Web services, like the World Wide
Web as a whole, are powerful because they allow content to be used in
unanticipated ways. Before you consider adopting UDDI for your
business, make sure that more than one implementer for each of the
standards being implemented exists. Otherwise, the
standard's "openness" is illusory, and vendor lock-in remains a
possibility. Be open, but be skeptical. If customers adopt only
standards that are truly open, then vendors will compete on
implementations, not on controlling customers' access to their own data.
You can find more information about UDDI at the UDDI Web site, as well
as at the other resources below.
