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To get the approved assurance profiles from metadata you need to activate the Metadata Attribute Extraction extension in Shibboleth SP. This is done by extending the ApplicationDefaults tag in Shibboleth2.xml by adding metadataAttributePrefix="Meta-" after REMOTE_USER="...", see example. This is a standard example in the file example-shibboleth2.xml in later versions of Shibboleth SP. It is also included in the SWAMID Configure Shibboleth SP - SWAMID-shibboleth2.xml

<ApplicationDefaults
    entityID="https://example.com/shibboleth"
    REMOTE_USER="eppn persistent-id targeted-id"
    metadataAttributePrefix="Meta-">

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Next step is to make approved assurance levels available in the application. This is done attribute-map.xml the same way as normal Identity Provider asserted attributes. It is also included in Configure Shibboleth SP - attribute-map.xml

<Attribute name="urn:oasis:names:tc:SAML:attribute:assurance-certification" id="Assurance-Certification"/>

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