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The goal of Federated Error Handling is ..to provide a better user experience in the case where an IdP provides an SP with insufficient information to make an access control decision.
The InCommon Federation now operates a centralized Federated Error Handling Service that SPs can use to generate simple but effective error pages for end usersthe end user. Such a page displays the public error handling URL for a given IdP. Alternatively, the Service will determine the error handling URL for a given IdP, and then return that URL it to the SP for further processing, so that the SP can roll its own error handler.
The InCommon Error Handling Service is hosted deployed on the same infrastructure that hosts InCommon metadata and the InCommon Discovery Service. All of these services are available 24x7 with manual failover to a redundant hot spare in the event of an outage.
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