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How do I configure an IdP to release attributes to R&S SPs?
To release attributes to all current and future R&S SPs with a one-time configuration, an IdP leverages entity attributes (instead of entity IDs). Thus the configuration steps documented in the R&S IdP Config topic require Shibboleth IdP v2.3.4 or later, which fully supports using entity attributes in SP metadata as part of an attribute release filter policy.
No other SAML IdP software is known to support entity attributes at this time.
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