h2. InCommon Entity Categories

h3. Terminology

* An _Entity Category_ is an Entity Attribute with @Name {nl:http://macedir.org/entity-category} and @NameFormat urn:oasis:names:tc:SAML:2.0:attrname-format:uri.
* An _Entity Attribute_ is a SAML Attribute in a container of type *mdattr:EntityAttributeType* defined by an Entity Attribute Profile of SAML Metadata.
* An _Entity Attribute Profile of SAML Metadata_ describes how SAML Attributes and Assertions can be added to SAML metadata extensions.
* An _Entity Category Profile of SAML Entity Attributes_ describes a specific Entity Attribute for categorizing entities according to some Entity Attribute Profile of SAML Metadata.

The first international _Entity Category Profile of SAML Entity Attributes_ in the R&E space is the [REFEDS Research & Scholarship|http://refeds.org/category/research-and-scholarship] Entity Category.

h3. Service Categories

{div:style=float:right;margin-left:1em;margin-bottom:1ex}{note}Browse a list of [all entity categories|https://incommon.org/federation/info/all-entity-categories.html]{note}{div}

A Service Category is a special type of Entity Category. A _Service Category_ is a group of service providers with a common purpose. The intended goal of a Service Category is to make attribute release more scalable. To this end, IdPs release a known set of attributes to entire categories of SPs. Using [entity attributes|Entity Attributes] (instead of entityIDs), attribute release policy at the IdP is configured for *all* services in the category (both present and future), rather than once per service. IdPs signal their support of particular service categories in metadata, which allows SPs to build dynamic, relevant discovery interfaces.

To become a member of the [Research and Scholarship Category], a service provider supports the research and scholarly activities of the higher ed community and satisfies a modest set of technical requirements.

h3. Resources

* The [SAML V2.0 Metadata Extension for Entity Attributes|https://wiki.oasis-open.org/security/SAML2MetadataAttr] is a standards-based _Entity Attribute Profile of SAML Metadata_.
* Entity Category Profile of SAML Entity Attributes