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A useful document on this: https://spaces.ais.ucla.edu/display/uctrustwg/ConfiguringScopedAttributes
This project was discussed in the context of the risk management application run under the Office of Risk Services at UC Davis. It is actually the kind of URN that is the issue at hand. In the early days of Shibboleth, people felt that the attributes should have human friendly names. But now, an OID (object identifier) is used. An OID is an LDAP designation of a string of numbers, like a hierarchical namespace except that everything is numerical. Each org is assigned a certain prefix of numbers so that it is certain that the OID’s are unique.
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