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- IdP does not support HTTP or HTTPS with at least SSLv3 or TLS1 or newer (these IdPs are insecure anyway)
- IdP is part of a Hub & Spoke federation (page in Federation, update link)(some of them manually have to first approve eduGAIN SPs)
- IdP does not use web-based login form (e.g. HTTP Basic Authentication or X.509 login)
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