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The Key Link Between EPPN and Provisioning Feeds
Most Cloud Service Providers cloud service providers require the college to regularly send flat files (or sometimes have sync or realtime connections) to the Could Cloud Service Provider that identify all the users from that college that should have access to that service. The Could The Cloud Service Provider defines a set of fields that you need to fill in for each user. One of those fields will be defined to be the "user id" for that service. That "user id" becomes the key field, the "username", for that user in the Cloud Service Provider user datastore.
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