FirstDigital Customer Knowledge-base

STIR/SHAKEN | Overview and FAQs

If you’ve ever used a phone, you know that many of the calls you receive are spam/scam calls. In 2018 alone, over 29% of calls were spam calls and it’s only continued to rise. Think about that: three years ago, almost one in every three calls was spam.

To help curb these issues, a set of protocols has been introduced and implemented known as STIR/SHAKEN. As of June 30 (2021), these standards have been implemented across most major carriers and telephony providers, as required by the FCC (US) and CRTC (Canada). The suite of protocols is designed so that it can be implemented in carriers outside the US and Canada as well.

For smaller and rural carriers, the FCC has mandated that STIR/SHAKEN be implemented no later than June 30, 2022. Please continue reading for answers to frequently asked questions regarding these new protocols and standards.

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A set of protocols and mechanisms to help mitigate the rise of spam/scam calls across the world. In 2018, it’s estimated that over 29% of calls were spam calls. Up from less than 4% the previous year.

What are Spam Calls?

Spam calls refer to unwanted calls. This can be as simple as a sales call or as cautionary as a scam call. A scam call refers to calls surrounding fraudulent activity.

Can’t I Just Block the Number the Caller is Using?

Yes and no. If the call is a sales call or from an unwanted organization, you can block the number (although calls may still be sent to voicemail). However, many spam calls are placed using spoofed numbers, so they aren’t actually calling from that number. Blocking a spoofed number may result in blocking legitimate calls and will not keep the spammer/scammer from calling you by spoofing a different number.

What is Number Spoofing?

Number spoofing allows callers to change their caller ID. This lets spammers make the call look like it’s coming from any number they choose.

What are Robocalls?

Robocalling can refer to calls that are placed automatically and/or use a prerecorded message or voice recognition and prerecorded messages to communicate.

What is STIR?

STIR (Secure Telephone Identity Revisited) adds information to the header of the incoming data used when placing and receiving calls. This information allows both endpoints to verify/identify the origin of the caller. It does not keep calls from being spoofed; however, it does allow the receiver to verify whether or not the call is trustworthy.

What is SHAKEN?

SHAKEN (Signature-based Handling of Asserted information using toKENs) helps define how to verify the calling number and how the call will be routed across communication networks. Together with STIR, these protocols and mechanisms are used to verify the origin of a call using what is called “attestation.”

What is attestation?

Attestation refers to three levels of verification within the STIR/SHAKEN protocol.

What are the levels of attestation?

There are three levels of attestation:

Full Attestation

  • If full attestation is awarded, the service provider can authenticate that a customer is authorized to use the number they are calling from.

Partial Attestation

  • If partial attestation is awarded, the service provider can authenticate the customer that originated the call; however, they are unable to verify this customer is authorized to be using the calling number.

Gateway Attestation

  • If gateway attestation is awarded, the service provider can authenticate the call’s origination, but they cannot verify the source of the call. This level of attestation is usually awarded to international gateway calls.

Does attestation guarantee verified identification is always accurate?

The levels of attestation represent the confidence that the caller’s identification is accurate; however, it isn’t always as simple as that. When a call appears to be inauthentic, it may just be coming from an unverifiable—but legitimate—source.

How do the different levels of attestation work?

Here is a quick explanation of each level of attestation:

Full Attestation

  • The carrier is responsible for originating the call.

  • The carrier has a preexisting direct relationship with the originating caller and can authenticate their identity.

  • The carrier can verify an association with the calling number.

Partial Attestation

  • The carrier is responsible for originating the call.

  • The carrier has a preexisting direct relationship with the originating caller and can authenticate their identity.

  • The carrier cannot verify an association with the calling number.

Gateway Attestation

  • The carrier is not considered the entry point (EP) of an incoming call to a VoIP network.

  • The carrier does not have an existing relationship with the caller

  • The carrier cannot verify the calling ID and is only able to determine the entry point on the network.

What does attestation mean for your call traffic?

The attestation process involved in STIR/SHAKEN is crucial for increasing your outgoing call traffic. If your business makes plenty of customer calls—especially cold calls—to new potential clients, the attestation standards may encourage some customers to pick up the phone.

This happens because the attestation process can result in a “valid call” symbol, which may encourage customers to pick up the phone from a business they trust. Of course, it can also discourage them if they suspect it’s a sales call. The attestation process gives providers the necessary information to determine call treatment for each call.

New developments in STIR/SHAKEN standards should further improve the attestation process.

When it comes to incoming calls, your business will also benefit from reduced spam calls. This process can help your employees identify fraudulent and spam calls, helping to reduce exposure to scams.

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For any questions, please contact Customer Support at (800) 213-1315 or (801) 379-3000.