Homeland security works to build resilience in nation’s digital infrastructure

The Department of Homeland Security’s (DHS) Science and Technology Directorate (S&T) has released its Best Practices for Resilient Positioning, Navigation, and Timing (PNT) Supporting Critical Infrastructure, a guide developed in response to Executive Order 13905, Strengthening National Resilience Through Responsible Use of Positioning, Navigation, and Timing Services.

The guide confronts the growing vulnerabilities in America’s critical infrastructure that relies heavily on PNT services, particularly the Global Positioning System (GPS).

As a cornerstone of national infrastructure, GPS enables precision timing and navigation across sectors such as finance, transportation, communications, and emergency services. However, its low-power, unencrypted space-based signals remain highly susceptible to jamming, spoofing, and both accidental and deliberate disruptions.

The S&T guide seeks to operationalize the resilience goals set by the executive order by offering actionable strategies for service providers, critical infrastructure operators, and technology developers. Its purpose is to encourage the adoption of secure and diversified PNT practices that mitigate the risks of dependency on a single source like GPS. The guide is framed to be use-case oriented and risk-informed, recognizing that effective resilience must account for a wide spectrum of threats and sector-specific vulnerabilities.

“Accurate and precise positioning, navigation, and timing information is vital to the nation’s critical infrastructure and is the backbone of the many services we depend on daily, from keeping our lights on to ensuring planes land safely,” said Julie Brewer, DHS Acting Under Secretary for Science and Technology. “This new toolset gives people responsible for safeguarding these systems a way to independently test and strengthen them, ensuring our nation’s infrastructure is more secure against potential disruptions.”

The document walks through several core areas intended to help organizations better understand their PNT dependencies and take strategic steps to bolster resilience. Among these, it emphasizes the importance of conducting thorough risk assessments to determine where and how PNT services are used within operational systems.

Understanding these dependencies allows organizations to evaluate the potential consequences of signal disruption and identify the most critical points of vulnerability. It also underscores the need to design PNT-reliant systems with resilience in mind, encouraging the use of secure architectures, encrypted communications, authenticated signals, and equipment capable of detecting and responding to signal anomalies.

Equally important, the guide promotes the integration of complementary and alternative timing technologies to avoid overreliance on GPS. This includes terrestrial systems, local atomic clocks, secure network-based timing, and emerging technologies such as Low Earth Orbit satellite PNT. By diversifying the timing sources used within critical infrastructure, organizations can better withstand or recover from interruptions in primary PNT signals.

In addition to technical strategies, the best practices provide procurement guidance that encourages infrastructure operators to incorporate resilience and redundancy requirements into vendor evaluations and system specifications. Operators are advised to seek out PNT solutions that are not only accurate, but are also robust under degraded conditions. This extends to regular system testing, simulation exercises, and training staff to recognize and respond to anomalies in timing data or location services.

The guide also includes practical examples tailored to specific infrastructure sectors. For example, communications networks are reminded of their need for precise timing to maintain call synchronization and data throughput.

Financial systems require sub-millisecond timing for transaction validation and regulatory compliance. Power grids depend on PNT data to synchronize phase angles, manage loads, and isolate faults, while transportation systems rely on GNSS for route planning, collision avoidance, and logistics. Any disruption in these timing systems, even for a short duration, could result in cascading failures with significant operational, economic, and safety consequences.

The release of the best practices complements a broader array of federal initiatives aimed at securing the PNT ecosystem. DHS has been deeply involved in interagency collaboration through the PNT Executive Committee which coordinates GPS-related policy across the Departments of Defense, Transportation, Energy, and DHS.

These partnerships also include coordination with the National Risk Management Center at the Cybersecurity and Infrastructure Security Agency, which conducts systemic risk assessments that include PNT-related vulnerabilities.

Additional efforts such as the GPS Backup Technology Demonstration Program have explored commercial alternatives to GPS, assessing whether new or existing technologies can fill gaps in resiliency.

While the guide represents significant progress, challenges remain in the implementation of resilient PNT practices. Many critical systems were built with GPS as their sole timing source, and retrofitting them to accommodate redundancy can be both technically and financially demanding. Smaller operators, especially in the utilities or transportation sectors, may lack the expertise or resources to evaluate new solutions, even when they recognize the risks.

Furthermore, without regulatory mandates or clear economic incentives, some operators may delay necessary upgrades until a disruption causes irreversible damage. This reactive posture, rather than a proactive strategy, remains one of the biggest barriers to widespread adoption of resilience principles.

Another dimension of this challenge is market inertia. In many cases, vendors of timing or navigation hardware do not prioritize resilience features unless they are directly requested by the buyer.

DHS S&T has encouraged public and private sector partners to integrate the best practices into their procurement and compliance frameworks, but enforcement remains voluntary unless tied to grant conditions or sector-specific regulation.

This makes ongoing engagement with industry essential, not just to promote uptake of the guidance, but to co-develop standards and shared benchmarks that will define what a “resilient” PNT system looks like in practice.

Public-private partnership is the linchpin in making these best practices effective. DHS has repeatedly emphasized that true resilience cannot be achieved through government policy alone. It must be built collaboratively, with input from those who operate and maintain the infrastructure on a daily basis.

Sector-specific Information Sharing and Analysis Centers are encouraged to help disseminate the guidance and translate its general recommendations into tailored implementation plans. Industry consortia, equipment manufacturers, and standards-setting bodies must also play a role in embedding resilience into the DNA of future PNT systems.

Looking ahead, DHS and its partners are likely to continue expanding their focus beyond GPS alone, especially as new commercial and military PNT constellations emerge. The development of Low Earth Orbit PNT systems offers a promising path forward, with faster refresh rates, stronger signals, and greater resistance to spoofing or jamming.

Meanwhile, terrestrial alternatives like eLORAN and fiber-optic timing distribution offer compelling solutions in localized or secure environments. A mix of satellite and ground-based technologies may ultimately provide the layered resilience that critical infrastructure sectors require.

The release of the Best Practices for Resilient PNT signals a larger shift in the way timing and navigation are conceptualized within the framework of national security. Once regarded as passive background services, these systems are now understood to be operational dependencies whose disruption can compromise everything from emergency dispatch to market stability.

As cyber-physical threats evolve and infrastructure digitization deepens, the capacity to maintain accurate, trusted PNT data, even under degraded conditions, will define the future of secure, resilient public infrastructure.

For DHS, this is not merely a technical issue but a strategic imperative. The guidance is designed to catalyze a culture of preparedness and foresight. Whether or not it succeeds will depend on the will of operators to act before a crisis, and on the government’s continued investment in cross-sector innovation, industry outreach, and scalable technology solutions.

In parallel with the release of the best practices guide, S&T has been advancing a suite of technologies specifically designed to empower first responders in complex and evolving environments. One of the most promising of these technologies is DePLife, a radar-based device that allows law enforcement and rescue teams to detect human presence behind walls without the need for physical entry or line-of-sight.

Originally developed in collaboration with MaXentric Technologies, DePLife is undergoing extensive field testing with agencies across California, Texas, and South Carolina. The technology has shown particular promise during breaching operations, hostage rescues, and counter-human trafficking efforts.

DePLife operates by transmitting radar pulses that bounce off objects inside a room. What distinguishes it from other technologies is its sensitivity to micro-movements such as a person’s breathing that static objects do not produce. This allows the device to detect life through materials like sheetrock and stucco, though metal walls remain a challenge.

Through iterative development cycles driven by first responder feedback, the prototype has been refined for ruggedness, ease of use, and reliability. As S&T Program Manager Anthony Caracciolo explained, the key to its success lies not only in technical precision but in building trust with the end users. “If it’s telling me it’s empty,” Caracciolo said, “it better be.”

Article Topics

biometrics  |  DePLife  |  DHS S&T  |  GPS  |  person detection  |  research and development