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The user's identity is transmitted in the form of the NameID element. Every IdP must supply a NameID, but for privacy reasons SURFconext will generate a new one, which is duplicated in the attribute eduPersonTargetedID.
To identify a user you the Service Provider must use NameID or eduPersonTargetedID. NameID is guaranteed to be stable for a fixed user (except in the case of transient identifiers). SURFconext will generate a NameID for each new user. It is unique for the user and specific to the SP, so SP's cannot correlate their received NameID's between each other. There are two types of NameIDs:
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