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Finally, note that the value of ePTID depends on the configuration as well. The actual User ID asserted by Google does not change, but the entityID values do change, depending depends on who is asserting the attributes. In Configuration 1, the Google IdP is the asserting entity and the ePTID reflects that. OTOH, in Configuration 2, the Gateway is the asserting entity and the ePTID reflects that as well.
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