The <mdrpi:RegistrationInfo/> element identifies the registration authority (i.e., the entity's federation) that enrolled this entity as the value of the XML attribute registrationAuthority. For InCommon-registered entities, that value is always "https://incommon.org/". For entities registered by other federations, it will contain a value that uniquely identifies that federation (available via https://technical.edugain.org/status).
Example:
<mdrpi:RegistrationInfo registrationAuthority="https://incommon.org"/> |