AAI: systematically addressing the attribute release problem

CLARIN Service Provider Federation is not the only inter-federation but it is the first one to systematically address the attributes release issue; when Identity Providers do not release mandatory attributes to a service. For instance, if a data set is licensed under a restrictive license the user must be uniquely identifiable over time. However, if the Identity Provider does not release such information, the service cannot let the user download the data.