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Service providers that have implemented STIR/SHAKEN can request these headers to be sent by Creating a Support Ticket. Please be ready to include the list of Endpoint Groups that you would like to receive the headers for.
Inbound Verification (STIR/SHAKEN verification results)
You may configure Inbound Verification at the Endpoint Group-level. The options are verstat, which sends STIR/SHAKEN verification results in the P-Asserted-Identity field, or header, which passes the entire STIR/SHAKEN header to your network (TCP Transport Type is recommended for this). For more information, please see our Wiki article on Endpoint Groups.
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