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SAML Naming Conventions
It 's is strongly recommended that URIs be used for attribute naming in SAML 2.0 attribute statements because of the uniqueness and namespace control they provide. Using non-unique strings as names is a discouraged practice because it presumes that every set of Attributes is configured specifically for each pair of interoperating IdP and SP, and that is not how SAML was meant to be used, though it is how most commercial implementations approach the standard.
The URI-based name of an attribute is expressed as the Name in the following example:
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