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IdP entityID: https://google.gateway.incommon.org
SP entityID: https://fm.incommon.org/sp
User ID: opaque_value
where opaque_value is computed by the gateway based on the IdP entityID, the SP entityID, and the persistent value 26dn84xIqIvilVMqYCPhE.
Discussion
It is important to note that Google email addresses do not always end in “@gmail.com”. In fact, a Google email address can be virtually anything since Google Apps accounts are based on arbitrary DNS domains.
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