STIR/SHAKEN — Secure Telephone Identity Revisited / Signature-based Handling of Asserted information using toKENs
What is STIR/SHAKEN?
STIR/SHAKEN is the US telecom framework that cryptographically signs a call's Caller ID so the terminating carrier can verify where the call actually originated before it rings. Every call carries an attestation level — A (full attestation), B (partial), or C (gateway) — and carriers weigh that signal, alongside reputation, when deciding whether to label a call “Spam Likely” or block it outright. Higher attestation generally means a higher answer rate.
More detail
Full (A) attestation means the originating carrier both authenticated the caller and confirmed their right to use the calling number. Partial (B) attestation confirms the caller but not the number's ownership. Gateway (C) attestation applies to calls entering the network from an unverified source, such as an international gateway.
Orbit tracks each outbound number's attestation tier and the answer-rate lift that tier earns over time, so a customer can see their attestation mix rather than a single static badge.
Frequently asked
- What does a STIR/SHAKEN attestation level mean?
- It tells the receiving carrier how much the originating carrier could verify about the call: A (full) confirms both the caller's identity and their right to the calling number, B (partial) confirms only the caller, and C (gateway) applies to calls entering from an unverified source.
- Does a low attestation level mean my calls get blocked?
- Not automatically, but a lower tier makes a call more likely to be labeled or filtered by the terminating carrier's spam analytics, which is why answer rates typically improve as attestation moves from C toward A.
See also
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