3GPP APIs Support Expanded STIR/SHAKEN Call Authentication Functionality

Achieving global interoperability helps reduce illegal robocalls and restore trust to the phone

The need for increased functionality, along with growing global adoption, is driving enhanced STIR/SHAKEN API development. Earlier this year, TransUnion released availability of a reference implementation for call authentication testing that complies with the latest Third Generation Partnership Project (3GPP) STIR/SHAKEN Application Programming Interfaces (APIs). This extensible set of APIs will help carriers around the world more easily make use of advanced capabilities and comply with regulatory mandates to combat illegal robocalling.

APIs are software intermediaries that allow applications from multiple vendors to talk to each other — in this case, to securely validate caller identity and stop illegal caller ID spoofing. These most recently published 3GPP RESTful APIs — and our reference implementation — extend the original Alliance for Telecommunications Industry Solutions (ATIS) standard (ATIS-1000082) which defines the most widely deployed set of STIR/SHAKEN APIs today.

The 3GPP RESTful APIs are formally defined in Technical Specification (TS) 24.229 (Annex V) and reflect a broad range of approved Change Requests over the past year.  

Get in on the action

Since the release of our reference implementation earlier this year, multiple vendors have conducted various levels of testing. TransUnion makes testing against the reference implementation available to interested parties at no charge. We’ll continue leading collaboration and consensus efforts to further enhance the 3GPP APIs as industry standards outpace carrier adoption.

For example, work has begun to design how best to add Rich Call Data (RCD) support to these APIs. RCD builds on caller ID authentication and unleashes a global carrier opportunity to extend caller ID and call-specific information beyond human-readable display names. Such information, when securely delivered and displayed on an end user’s device, has been shown to increase call answer rates and is helping restore trust in phone calls.  

The standard 3GPP APIs can also be viewed as a cost-savings measure, eliminating the need for vendors and carriers to deploy and maintain proprietary interfaces for STIR/SHAKEN call authentication and other related enhancements. Thus, we strongly encourage carriers interested in using a standards-based call authentication approach to promote further testing and vendor collaboration with us and others already participating in this effort.

More features, more functionality

The 3GPP APIs are especially important given STIR/SHAKEN industry standards have significantly outpaced associated API standards development. For example, the published APIs from ATIS only address basic STIR/SHAKEN call authentication as specified in ATIS-1000074, but do not address more complex call types that are being currently exploited by scammers like call forwarding and emergency services.

Expanding global adoption

The 3GPP APIs are also important given global developments over the last year or so. STIR/SHAKEN call authentication is no longer limited to just North America as regulatory mandates and interest have spread into most all other world continents. The STIR/SHAKEN APIs originally published by ATIS didn’t contemplate such compliance and interoperability of international cross-border calls. 

An extensible, standards-based approach

At TransUnion, we believe a standards-based collaborative approach for such development will be most beneficial to all industry participants. Our reference implementation, and joint industry testing conducted to date, demonstrate the 3GPP APIs represent a solid, extensible foundation upon which to build for the future.

Visit our GitHub site for details on our reference implementation, along with working 3GPP API examples.

Learn how TruContact™ Caller ID Authentication, Powered by Neustar®, helps enterprises and communications service providers (CSPs) certify calls using STIR/SHAKEN call authentication to reduce call spoofing and fraud.