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Before configuring the IdP to communicate with a service provider be sure you have a basic understanding of how the IdP categorizes and works with service providers.
Communication Basics
In the most of cases enabling communication with a service provider requires:
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Loading the SP's metadata can be accomplished in a couple different ways. First, and easiest, is for the service provider to register with a federation whose metadata is already being loaded by the IdP. In this case the IdP will receive the SPs metadata at its next metadata refresh (this occurs once a day by default). Alternatively the IdP may establish some bi-lateral bilateral process for receiving the SPs metadata. For example, it may use the file-backed HTTP metadata provider to retrieve it from an SP provided URL.
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