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  1. Science and Technology Directorate
  2. News Room
  3. News Release: DHS Publishes Critical Infrastructure Protection Resources

News Release: DHS Publishes Two Free Resources to Protect Critical Infrastructure from GPS Vulnerabilities

Release Date: October 7, 2021

S&T Public Affairs, 202-254-2385

WASHINGTON – The Department of Homeland Security (DHS) Science and Technology Directorate (S&T) announced today it has published a Global Positioning System (GPS) Receiver Whitelist Development Guide and a new release of the Positioning, Navigation, and Timing (PNT) Integrity Library to protect against the spoofing, or deceiving, of GPS devices through false signals. These resources advance the design of PNT systems and increase resilience of critical infrastructure to PNT disruptions.

The GPS Whitelist Development Guide presents a software assurance approach to addressing potential vulnerabilities and increasing reliability of GPS receivers. The guide addresses data-related requirements in the Resilient PNT Conformance Framework, which provides guidance for defining expected behaviors in resilient PNT equipment.

“We hope this guide and related resources will help industry advance towards a cybersecurity-based approach to PNT resilience,” said S&T Technical Manager Ernest Wong.

Originally released in March 2021 as open source on GitHub, the PNT Integrity Library provides users with a method to verify the integrity of the received GPS data. The update includes:

  1. A compliance check on Interface Control Document (ICD) IS-GPS-200, which is a formal means of establishing, defining, and controlling communication between the GPS space and other user systems; and
  2. A Do-It-Yourself (DIY) Toolkit, which describes how a perspective end-user of the PNT Integrity Library can assemble a demonstrational toolkit with commercial-off-the-shelf (COTS) hardware.

“Since GPS signals can be jammed or spoofed, critical infrastructure systems should not be designed with the assumption that GPS data will always be available or will always be accurate,” said S&T Project Manager, Brannan Villee.  “Application of these tools will provide increased security against GPS disruptions. However, DHS also recommends a holistic defense strategy that considers the integrity of the PNT data from its reception through its use in the supported system.”   

The PNT Integrity Library and GPS Whitelist Development Guide are available free of charge. To view more details on the DHS S&T PNT Program, visit https://www.dhs.gov/science-and-technology/pnt-program.


Last Updated: 10/07/2021
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