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We recommend that InCommon assign uris URIs to the profiles it defines, specifically, that they assign "urn:mace:incommon:iap:bronze" to the bronze identity assurance profile, and "urn:mace:incommon:iap:silver" to the silver profile. MACE-Dir could define an attribute, identityAssuranceQualifier, whose value would be one of the two URIs defined above (or the value"urn:mace:dir:constant:test"). This attribute could be one element of a SAML attribute assertion, and the SP would then have information on the identity assurance of the assertion as a whole.