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The SAML AA implements the SAML attribute Query protocol. It is basically a Shibboleth IdP which reads attribute data from MySQL.
(Example implementation, see https://wiki.surfnet.nl/display/ORCIDAA/Technical+Setup, chapter 2)
VOOT AA
the VOOT AA is a RESTfull, OAuth2 shielded resource providing group and attribute information using the VOOT protocol. Example implementation (https://github.com/OpenConextApps/php-voot-provider)
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