http://spaces.internet2.edu/Shibboleth.sso/Metadata spaces.internet2.edu.crt
http://discovery.shibboleth.net/shibboleth.net-metadata.xml
#https://www.dreamspark.com/policies/dreamspark_metadata.xml
https://login.terena.org/wayf/module.php/saml/sp/metadata.php/default-sp?output=xml
https://kantarainitiative.org/shibboleth/metadata.xml