Definition
STIR/SHAKEN is the caller ID authentication framework the FCC has required of major U.S. voice providers since 2021, which cryptographically attests that a call's originating number was not spoofed in transit.
The originating provider signs each call at one of three attestation levels (A, B, or C), and the terminating provider verifies the signature. The framework was mandated under the TRACED Act to fight illegal spoofed robocalls. It works only where calls stay on IP networks: when a call crosses a legacy TDM or SS7 segment, the authentication data is stripped, and the FCC calls those non-IP segments the largest obstacle to universal coverage.
Authentication is not identity. STIR/SHAKEN can verify that a call genuinely comes from the number displayed, but it says nothing about who owns the number or why they are calling, and the patient never sees the signature. Transaction Network Services' mid-2026 report found 17% of confirmed spoofed calls carried "A"-level attestation, and the FCC's December 2025 triennial review record includes providers assigning "A" attestation to invalid or Do Not Originate numbers.
For a healthcare caller, STIR/SHAKEN is table stakes, not a deliverability strategy. Getting answered also takes number reputation management, branded caller ID, and screener-aware calling. The FCC's October 2025 proposal on call branding, using Rich Call Data as the identity extension to STIR/SHAKEN, acknowledges that attestation alone has not given consumers a reason to answer.
How Consig handles it
Consig handles caller ID, number reputation, and dialing patterns behind the scenes, working through carrier relationships and strategic partnerships, so authentication is one layer of getting a call answered rather than the whole strategy.