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If a Service Provider requests a particular R&S attribute, the Identity Provider is REQUIRED to release it. Thus one or more R&S attributes MUST be listed in Service Provider metadata, otherwise the Identity Provider may release nothing at all.
If a Service Provider requests an Service Providers SHOULD request a subset of R&S attribute in metadata, that attribute MUST be required to operate the service. Thus an attributes that represent only those attributes that the Service Provider requires to operate its service. Such an R&S attribute requested in metadata MUST NOT be decorated with isRequired="false". Beyond that, the use of the isRequired XML attribute on any <md:RequestedAttribute> element in metadata is unspecified.
7. Attribute Release
An Identity Provider supports the Research & Scholarship (R&S) category if, for some subset of the Identity Provider’s user population, the Identity Provider is willing and able to release the R&S attribute bundle to all conforming R&S Service Providers without administrative involvement, either automatically or subject to user consent.
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