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There are three levels of attestation:
Full Attestation
If full attestation is awarded, the service provider can authenticate that a customer is authorized to use the number they are calling from.
Partial Attestation
If partial attestation is awarded, the service provider can authenticate the customer that originated the call; however, they are unable to verify this customer is authorized to be using the calling number.
Gateway Attestation
If gateway attestation is awarded, the service provider can authenticate the call’s origination, but they cannot verify the source of the call. This level of attestation is usually awarded to international gateway calls.
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