Contact Us

STIR/SHAKEN

Combat fraudulent robocalling

Technology framework to reduce spoofing

In order to decrease illegal robocalls, a framework has been designed to ensure the calling number is secure. The protocol is referred to as STIR/SHAKEN.
Fraudulent robocalls and illegal phone number spoofing have generated millions of unwanted calls. In order to reduce them, a framework has been created to make sure the calling number of a telephone call is secure. This is referred to as STIR/SHAKEN.
STIR/SHAKEN uses digital certificates based on common public key cryptography techniques. Each telephone service provider obtains their digital certificate from a trusted authority. This certificate technology enables the called party to verify that the calling number is accurate.
Codeflex Labs Inc., dba Sipswitch’s call authentication service will provide you with the tools to ensure your calls are not flagged as unwanted spam and delivered to end users’ phones without impairment.

STIR/SHAKEN DEFINED

What is STIR?
Secure Telephony Identity Revisited (STIR) is a working group within an internet standards body, which has developed a set of protocols used to create a digital signature for a call. The signed call includes information about the calling party and allows for verification of the signature by the terminating provider.
What is SHAKEN?
Signature-based Handling of Asserted Information Using toKENs (SHAKEN) are the standards for how STIR is deployed by service providers within their networks.

HOW STIR/SHAKEN WORKS

  • 1. A SIP invite is received by the originating telephone service provider.
  • 2. The originating service provider checks the call source and calling number to determine how to attest the validity of the calling number (i.e. full, partial, gateway).
  • 3. The originating service provider uses the authentication service to create a SIP Identity header.
  • 4. The SIP Invite with the SIP Identity header is sent to the terminating telephone service provider.
  • 5. The SIP Invite with Identity header is sent to a verification service.
  • 6. The verification service obtains the digital certificate of the originating service provider from the public certificate repository and begins the verification process.
  • 7. The verification service returns the results to the terminating service provider’s softswitch or SBC.
  • 8. The call is completed to the called party.

SHAKEN ATTESTATION

SHAKEN attestation is proof that a call is not fraudulent. It’s based on the originating service provider’s relationship to the telephone number. There are 3 different levels of attestation.

A. FULL

  • This is my customer. This call originated on my network. I gave them this telephone number.
The signing provider:
  • is responsible for the origination of the call onto the IP-based service provider voice network
  • has a direct authenticated relationship with the customer and can identify the customer
  • has established a verified association with the telephone number used for the call

B. PARTIAL

  • This is my customer. This call originated on my network. I did not give them this phone number.
The signing provider:
  • is responsible for the origination of the call onto the IP-based service provider voice network
  • has a direct authenticated relationship with the customer and can identify the customer
  • has NOT established a verified association with the telephone number used for the call

C. GATEWAY

  • This call originated outside my network.
The signing provider:
  • has no relationship to the initiator of the call (i.e. international)

HOW WE CAN HELP YOUR BUSINESS

Our service empowers you to:
  • Activate and deactivate call screening
  • Create and manage white and black lists
  • Assign call treatments for "Unknown Caller"
  • Build a white list from an imported file
  • Filter unwanted calls using subscriber-maintained lists, global lists, CAPTCHA tests and more
Changing & evolving
STIR/SHAKEN is an industry-wide initiative to restore trust in our voice communications. It utilizes a combination of technical, legal and behavioral solutions. It is an evolving process that continues to be refined in order to address the dynamic needs of the marketplace.
Expect upcoming improvements including the support of non-IP networks, enterprise multi-carrier implementation and standardization on how attestation is displayed on devices.
Taking proactive steps
Codeflex Labs Inc., dba Sipswitch Telecom started to implement STIR/SHAKEN in our network in 2020. We have established interoperability with major carriers and other enhancements that will support our customers’ compliance with STIR/SHAKEN.
Consolidating your outbound calling and phone numbers with Codeflex Labs Inc., dba Sipswitch can simplify your compliance with STIR/SHAKEN. As an Codeflex Labs Inc., dba Sipswitch voice customer, your calls are automatically signed with full attestation. This lowers the chance that your calls will be blocked by a terminating carrier.
Codeflex Labs Inc., dba Sipswitch continues to take proactive steps to prevent malicious forms of traffic from entering our network, while ensuring that valid traffic is protected. We are an active petitioner with the FCC. We advocate telecommunications policies on behalf of our customers.

Get in touch

Contact Us

Get in touch and we’ll get back to you as soon as we can.  We look forward to hearing from you!
  • Copyright © 2025 SIP Switch
Scroll to Top