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For an example on how to consume and process this information in an Identity Provider look at the page Example of a standard attribute filter for Shibboleth IdP v3.4.0 and above. ADFS Toolkit support the use of entity categories.

Attribute release comparison between REFEDS Entity Categories with fixed attribute bundles

REFEDS (the Research and Education FEDerations group) is the standard organisation within the academic identity federation community. To enable, simplify and minimalize attribute release from Identity Providers to Service Providers. A service should never ask for more attributes that they need for delivering the service to the end user. Based on this assumption REFEDS has created three new hierarchal entity categories where Anonymous Access is for services that don't need any personalized information, Pseudonymous Access is for services that support personalization between session but don't have any need of personal identifiable information and Personalized Access is for services that need personal identifiable information. You should use more than one of these entity categories for the same service. Research and Scholarship (R&S) is more or less the same as Personalized Access but have more restricted use cases and another set of identifiers. For services that needs other attributes than supported by the fixed attribute bundles the entity categories REFEDS/GÉANT Data Protection Code of Conduct is used.

REFEDS Anonymous Access Entity Category

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