STIR/SHAKEN - RoboCall Spoofing and Caller ID Authentication

What Does STIR/SHAKEN Mean?

STIR/SHAKEN is a framework of interconnected standards. STIR/SHAKEN are acronyms for the Secure Telephone Identity Revisited (STIR) and Signature-based Handling of Asserted Information Using toKENs (SHAKEN) standards. This means that calls traveling through interconnected phone networks can have their caller ID "signed" as legitimate by originating carriers and validated by other carriers before reaching consumers. STIR/SHAKEN digitally validates the handoff of phone calls passing through the complex web of networks, allowing the phone company of the consumer receiving the call to verify that a call is in fact from the number displayed on Caller ID.

How does STIR/SHAKEN help combat illegal and nuisance calls?

STIR/SHAKEN is a caller-ID authentication system using the same secure cryptographic techniques that keep your information safe when you interact with online shopping or banking websites and apps. It means that the service provider receiving a call knows how much to trust the caller-ID on the call.

By itself, it makes it harder for someone making illegal or nuisance calls to hide behind a fake caller-ID, and therefore more likely they will be caught, acting as a deterrent.

STIR/SHAKEN has other potential benefits when combined with robocall analytics and blocking services used by service providers: the fact that a call has or hasn’t been authenticated is another factor that can be used to help separate good calls from bad calls, making it more likely the good ones get through and the bad ones get blocked.

MTC uses Call Guardian Authentication Hub, a best-in-class combination of STIR/SHAKEN and robocall analytics from Metaswitch and TNS that provides protection against illegal and nuisance calls to our subscribers.

What types of calls are blocked?

MTC prevents both unwanted calls (such as political campaigns, charities) as well as fraudulent calls (such as IRS scams).

How does it work?

Unlike other features that only reject calls from a specific set of callers that you select, MTC validates the calling number against huge national databases of unwanted callers. Those databases are dynamically changing, and new calling numbers used by unwanted callers will be blocked within minutes of them starting to be used.

Is any configuration required?

No, you just need to opt in, and the feature then works automatically as described above.

Are all unwanted calls blocked?

MTC does not guarantee to block 100% of unwanted calls, but it will very significantly reduce the number that manage to get through.

Will it block any calls I do want to receive?

MTC uses highly intelligent algorithms to determine what calls to block. In particular it is carefully designed not to block calls from high volume callers that you still need to receive, such as mass announcements from schools to announce snow closures, or calls from hospitals to confirm appointments.