A taxonomy is a hierarchical classification scheme. In CentraSite, you use taxonomies to classify objects in the registry. Taxonomies enable you to filter, group, and sort the contents of the registry.

A taxonomy consists of a name and zero or more categories. A category represents a classification within the taxonomy. A category can have multiple levels of sub-categories.

A taxonomy categorizes assets in CentraSite so that a consumer can search for assets within a particular category. CentraSite provides several predefined taxonomies, which are available to all users. Additionally, you can create custom taxonomies to suit your business needs and subdivide them by creating categories. Categories help consumers locate assets more easily. For example, if you are offering assets to help your consumers better manage their finances, classifying your assets under personal banking or money management helps them locate your assets easily.

To create and manage a taxonomy, you must belong to a role that has the Manage Taxonomies system-level permission. By default, users with the CentraSite Administrator or Asset Type Administrator role have this permission, and can assign this permission to other roles. The Manage Taxonomies permission enables you to manage (create, view, edit, and delete) any user-defined taxonomy (the predefined taxonomies provided by CentraSite can be modified in certain ways, but cannot be deleted).

While publishing assets to CentraSite, they can be classified in two ways:

Classified assets are easier to locate because CentraSite includes convenient tools for filtering, reporting, and querying the registry by taxonomy. For example, the Browse page enables users to browse the asset catalog according to a specified taxonomy. The advanced search feature enables users to query the registry for assets that are classified in a particular way.

Design/Change-Time policies execute when events within the policy's scope occur in the registry. The scope of a policy specifies to which type of registry objects the policy applies (for example, Service objects, Policy objects, User objects) and during which type of events the policy is triggered (for example, a PreCreate event, a PostCreate event, a PreStateChange event).

Classifying assets helps you create highly targeted design/change-time policies, because the scope of a policy can be additionally constrained to objects that are classified in a specified way. For example, instead of applying a particular policy to all Application Server assets, you may restrict the policy to just the Application Server assets that are classified by the APAC category from the Domains taxonomy.

When you define a custom asset type, decide whether you needs to apply different design/change-time policies to specific subsets of that type. If so, ensure that the asset type includes a Classification attribute that can be used to distinguish those subsets. (Consider making this a required attribute to ensure that users do not forget to classify assets of this type.)

Like types, taxonomies are system-wide objects (that is, all organizations have access to the same global set of taxonomies). You cannot restrict a taxonomy to a specific organization.

Taxonomies are also visible to all users. All users (including guest users) can view the taxonomies defined within an instance of CentraSite.

CentraSite installs a number of standard taxonomies that you can use to classify assets.

These include:

CentraSite also includes a number of special-purpose taxonomies to support the use of CentraSite by products such as the webMethods product suite. These taxonomies belong to other products, which expect the taxonomy definitions to remain unchanged.

You cannot delete any of the predefined taxonomies installed with CentraSite or modify their category structure. Deleting these taxonomies in CentraSite can lead to inconsistencies or errors in the product that uses the taxonomy. For example, if you delete a taxonomy that is used by the webMethods product suite, components such as the webMethods API Portal may not be able to capture the original asset metadata from CentraSite. You can, however, modify certain attributes and properties for these taxonomies. Additionally, you can suppress them in the user interface. For example, if your users will never use the NAICS taxonomies that CentraSite provides, you can remove these taxonomies from the user interface.

In addition to using the taxonomies that CentraSite provides, you can create your own custom taxonomies.

When you include a Classification attribute in a type, you usually need to create a corresponding taxonomy for the attribute (unless the required taxonomy already exists in the registry). For example, let's say you decide that you want to classify your Application Server assets according to the domain in which they reside. To do this you would first create a custom taxonomy that identifies the various domains in your environment. Then, after the taxonomy exists, you would customize the Application Server asset type and add a Classification attribute to it that enables users to classify application server assets by the Domain taxonomy.

All users have implicit (and irrevocable) view permission on taxonomies. This permission enables any user to access any taxonomy for the purpose of classifying or filtering registry objects. However, taxonomies have the following additional properties that control whether they are visible to users within the CentraSite Control and CentraSite Business UI.