Taxonomies are a special registry data type identified by tModels. They are essential to the Description part of UDDI and are used to represent Category, Relational, and Identifier Systems. Taxonomy references are collected into registry records using bags of Keyed References. The Keyed Reference data type contains:
tModel Key - identifying the technical model desccribing the taxonomy referred to.
Key Name - a human-readable identifier the meaning of which depends on the taxonomy being used.
Key Value - a unique value for this reference the meaning of which depends on the taxonomy being used. It can be based on an algorithm or similar systemization aproach.
Taxonomies are designed to be handled either strictly or loosely. When devising key values some taxonomies use a highly structured system. If you know the rules, key values provide important indications about the nature of their subject. One analogy is a library catalog system where books identified by a value in the 900's would be about Geography or History while those in the 500's would be about Mathematics and Science.
Such taxonomies are considered as checked. Key values can be checked against an established naming algorithm or system.
Taxonomies that cannot be checked are considered as unchecked. Their values cannot be easily verified and must be taken within the system on good faith.
When working with taxonomies you will discover that checked ones will allow you to drill down through a tree or similar structure until you find the taxonomy you want. In the checked case you simply check a box and then another control to add a taxonomy to a Category or Identifier bag or similar container belonging to the record you are editing.
With unchecked taxonomies you simply enter the Key Name and Key Value by hand.
Several taxonomies are mandated by the specification to be included in any UDDI registry. Others come as a special part of the BEA AquaLogic Service Registry. Some of the more useful taxonomies include:
unspsc-org:unspsc:v6.0501 - United Nations Standard Products and Services Code. A checked Categorization system for Providers (Businesses) based on products and services the business provides.
ubr-uddi-org:iso-ch:3166-2003 - A checked Geographic Categorization System maintained by ISO and useful for establishing location.
uddi-org:general_keywords - An unchecked system in which Key Names are used like namespace identifiers and Key Values as unique values within the space. Policies for using this taxonomy should be established by users and administrators.
ntis-gov:naics:2002 - The checked North American Industrial Classification System maintained by the US Census department.
systinet-com:taxonomy:usage - An unchecked classification system included to let users declare intended use for the system entities represented by the record. Actual use policies should be established by users and administrators.
When publishing records, the more taxonomies used to describe them, the more discoverable they become.