New standard the UDDI was announced several years ago [see the history in Wikipedia]. The UDDI future was promising. I was sure for that. I thought, the future is for Web-services [WS], and it is. Isn’t that mean, we need services to search Web-services in internet, some Registries/Catalogs of the Web-services?
How we could find the WS in internet? Google Search was not effective in this; it is still not effective now. By any means, the UDDI idea should win; all WS-s should work with UDDI Registers. There was no way to live without UDDI. WS-s should be everywhere and to find the right one we should use the UDDI. We thought so.
The big companies started to invest in UDDI: IBM, Microsoft, SAP, and more. Smart people were writing UDDI standard, developers were writing UDDI systems. Big companies announced about public UDDI Registers in internet. Future was without clouds.
What happens after this? Several years ago Microsoft, IBM closed they UDDI Registers in internet. Now there aren’t big public UDDI Registers. We have some but they are miserable. Seems, nobody wants to publish the WS-s in these Registers.
Why the UDDI Registers are not popular as Google or Yahoo Search?
This all resembles to me the “pre-google” days, while each new site must be “promoted” into the search engines. We could register a new site in some engines without problems, in some engines only with payment or registration. Then the Google was born. Google is gathering new sites by itself and automatically included them to the Google register. Explicit procedures were changed to implicit, automatic procedures.
Maybe the same was happened with the Registers for WS-s?
But what was happened, the most of the WS-s did not want to be “promoted”. Most of the WS-s are created for the limited user audience. Those users know all information about the WS, its address, its meta-information (Wsdl, Wsd-s, bindings, etc.). Moreover it is unlikely anybody outside of the circle of the trusted users could access this information.
There were other reasons that let the UDDI standard go down.
One of the reasons was the standard itself. It was not simple, nor clear, nor easy to use standard. Creators make it all-embracing (maybe creators thought so) and designed in smallest details, big and clumsy. It was popular in these years creating internet standards in such fashion; include in standards all and everything. Standards of those years were set apart as monolithic and huge. Standards tended to include all knowledge of specific area. Of course, they were not as large as monster-standards like EDI or HL7. But they were not as laconic and segmented as modern standards (for example, the family of the WS-* standards).
But the most negative factor was the fact the UDDI was substituted by other more advanced technologies. Now most of the Web-services show the meta-information on the predefined URL. All Wsdl-s, Xsd-s, and bindings are placed together with Web-service not in specialized Registers. In this way the Web-service makes itself independent, self-describing. User didn’t have to search the WS meta-information somewhere else. Users need to know only the URI (address) of the WS. It is not wise to use UDDI Registers to store only addresses. UDDI Registers are too complex, too overloaded with unused functionality for this simple task.
As a result the UDDI standard and UDDI services are now used only in small, narrow areas. For example, the UDDI service is used in the Microsoft BizTalk Server (see ESB Toolkit 2.0). Web-service Register has to be in the ESB, because the whole idea of ESB is based on principle, that user is publishing messages in ESB and the Bus knows what services should process the messages, knows all addresses, knows all format transformations.
But if we are returning to the generic case of the Web-service, all we need to know is the address of this WS.
UDDI let us find the WS by key words as it is in the Yahoo Directories. It happens this feature is not a user requirement at all.
The UDDI standard in the niche standard not universal so far.
UDDI. Official site]
Why are IBM, Microsoft and SAP discontinuing the operation of the UDDI Business Registry]
UDDI in Microsoft]
BizTalk. ESB Toolkit 2.0. UDDI in BizTalk]