Ending Robocalls, Scam Calls, and Caller ID Spoofing

However, providers with less than 100,000 subscribers have until June 30, 2023 to implement STIR/SHAKEN. This is important because the FCC found that most illegal robocalls come from a subset of these small providers, which has prompted the agency to propose shortening the adoption period by one year.

We all hate Robocalls and scammers persistently calling our phones and you may have sensed an increase in the frequency of this common nuisance. You are correct.

So far in 2021, Americans have received a monthly average of 30.7 spam calls, compared to 28.0 in 2020, according to a June 2021 report from Truecaller. Robocalls represented 21.5 of the average monthly spam calls, or 70%.

In a matter of minutes, unsavory telemarketing groups at home and abroad can set up a PBX (Private Branch Exchange), upload a list of numbers, and begin robocalling their hapless callers. When you try to call back the number on your Caller ID to complain, you may receive a number-not-in-service error or a confused individual wondering why you are calling them.

How Does This Happen?
The issue is that spoofing phone numbers is as simple as typing any phone number into the outbound CID (Caller ID) field of your PBX.

What’s the Solution?
Enter STIR/SHAKEN (because we love acronyms). STIR/SHAKEN is a suite of protocols and procedures to address spoofing over VoIP (Voice over IP) and non-VoIP (cellphones and landlines).

STIR (Secure Telephony Identity Revisited) handles the most common means of spoofing– VoIP traffic– by adding a digital certificate to SIP (Session Initiation Protocol). SIP is the protocol that establishes and maintains VoIP phone calls. On the VoIP service provider end, the SIP trunk is authorized to send data with this CID. Upon authorization, an encrypted certificate with the trunk provider’s information as well as trust value of the data is attached to the SIP header. On the network where the call is being terminated, the message is decrypted using the origin provider’s public key.

SHAKEN (Signature-based Handling of Asserted information using toKENs) is a set of guidelines for PSTN (public switched telephone networks) for calls that have incorrect or missing STIR information.

Will It Make a Difference?
With the passing of the TRACED Act (Telephone Robocall Abuse Criminal Enforcement and Deterrence) in December 2019, the FCC announced that it expected all phone providers to adopt STIR/SHAKEN by September 30, 2020, which was extended to June 30, 2021.

At present, three major U.S. carriers have implemented STIR/SHAKEN: Verizon, AT&T, and T-Mobile.

However, providers with less than 100,000 subscribers have until June 30, 2023 to implement STIR/SHAKEN. This is important because the FCC found that most illegal robocalls come from a subset of these small providers, which has prompted the agency to propose shortening the adoption period by one year.