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Call attestation
The confidence rating a carrier attaches to a call under STIR/SHAKEN, saying how sure it is that you actually own the number you are calling from.
Call attestation is the confidence rating a carrier attaches to your call as part of stir shaken. When the originating carrier signs a call, it also says how sure it is that the calling number is really yours. That rating travels with the call and helps downstream carriers decide whether to trust it. Think of it as the carrier vouching for you, with three possible levels of how strongly.
The levels are usually written A, B, and C. Level A, full attestation, means the carrier knows exactly who you are and confirms you own the cid you are using. Level B, partial attestation, means the carrier knows you but cannot confirm the specific number. Level C, gateway attestation, means the call entered their network from somewhere they cannot vouch for. The higher the level, the better your calls tend to fare.
Why aim for level A
Calls with low attestation are far more likely to get a spam likely label, which tanks your answer rate. Phone companies treat weak attestation as a hint that the call might be junk or even caller id spoofing. So earning full attestation is one of the most direct ways to keep your calls looking legitimate to the networks that decide whether they ring through.
To get level A, your carrier has to verify that you genuinely control the ani numbers you dial from. That usually means using numbers the carrier provisioned for you, not arbitrary numbers borrowed from elsewhere. If your calls are being flagged, ask your carrier what attestation level they are giving you — it is often the missing piece behind low answer rates.
Related terms
ANI
ANI, short for Automatic Number Identification, is the phone number your call carries as its source, which the person you dialed usually sees as caller ID.
Caller ID spoofing
Caller ID spoofing is sending a false or misleading number on outbound calls so the recipient cannot see who is really calling, which is broadly illegal.
Carrier
A carrier is the phone company that actually carries your calls onto the public phone network — VICIdial dials, the carrier delivers.
CID (caller ID)
CID (caller ID) is the phone number you show on the screen of the person you're calling, set per campaign or per list in VICIdial.
Spam Likely label
A warning that phone carriers display on incoming calls they think might be unwanted, which sharply lowers how often people pick up your calls.
STIR/SHAKEN
A system carriers use to digitally sign caller ID, proving a call really comes from the number it claims, which helps cut down on spoofed and fraudulent calls.