Preparing for Cyber Attacks on GPS Systems
We are increasingly witnessing cyber attacks on GPS systems. How does this affect our lives and how is our organization set to continue its business operations if GPS collapses?
Focus Telecom, which provides consulting, synchronization solutions, and cyber defense for banks, security organizations, government offices, and high-tech companies, provides an answer | Shlomi Mazor
​​GPS has been an integral part of our daily lives already for a couple of years. Yet, we are unaware that many of the systems that surround us are synchronized via the Network Time Protocol (NTP), which is based on the time deriving from the satellite-based Global Positioning System (GPS), itself owned by the American government.
We are totally reliant on GPS, including for cellular antennas which route our calls, ATMs and credit cards, the power grid, airport control towers, digital television broadcasts, public transportation, data centers, etc.
In 2012, Newark International Airport (New Jersey) was disrupted for nearly two weeks because of a driver who activated GPS blocking in his car to avoid his boss. In 2013, the London Stock Exchange halted its activities for twenty-four hours due to a similar situation. In 2017, the navigation systems of twenty trade ships in the Black Sea reported that they were in an airport, despite being dozens of kilometers from land. In 2017, an airport in France was essentially disabled for a couple of hours due to a driver who forgot the GPS blocker in his car.
A Tangible Danger to Business Operations
The dependence of essential systems on GPS, as well as the relative ease to obstruct and disrupt satellite signals, has made GPS a clear target for hackers and terrorists.   
The American Congress estimates that the potential damage of any chaos arising from GPS systems to be 66 billion USD a year and instructed security officials in the USA to establish ground back-up systems.
The Israeli Cyber Authority in the Prime Minister’s Office will soon publish a request for information (RFI) to establish a national time infrastructure as a back-up to GPS. Until this infrastructure becomes available to networks throughout the country, it is incumbent upon all organizations to carefully examine the sources of time and synchronization that their essential systems rely on, and subsequently defend them. If an organization has no contingency scenario planned for a lack of availability/ reliability of GPS, then it has already tangibly exposed itself to dangers that can affect its business operations.
A Multi-Layered Defense Outlook

Focus Telecom has been specializing in synchronizing time systems since 1995 and provides time and synchronization solutions to governmental bodies, as well as security and business organizations. The company has developed a defense outlook for organizations based on nine layers, which generates an “Iron Dome” that prevents hackers from obstructing or disrupting the synchronization sources of an organization’s computing systems.

  • The Front-End Layer – The GPSDOME System: A unit based on Null Steering technology, which knows how to identify and neutralize interferences before they reach the servers. Satellites transmit GPS signals at a frequency of 1575 MHz at a distance of 20,000 kilometers from Earth. The GPSDOME system, which is about as large as a computer mouse, knows how to identify and disable illegal signals.
  • The Mask Layer – Software or hardware that knows how to identify the arrival angles of antenna signals. Each transmission that arrives from a precise enough angle deemed to be illegal is repulsed.
  • The Cutoff Layer – The external RF Switch unit, which was developed by Focus Telecom, knows how to automatically or manually connect and disconnect the GPS internet cable. The goal is to build an internal, quality oscillator and minimize the dependence on GPS as much as possible. The RFS Switch unit allows the synchronization equipment to execute satellite calibration for a long period of time, thereby reducing the exposure time for potential attacks. The moment a national warning is received, it allows you to remotely disconnect the GPS connection.
  • The Firewall Layer – Half a year ago, the company Microsemi launched Bluesky – the first firewall of its kind for GPS. Bluesky continually monitors RF data that enters an organization’s network and knows how to identify anomalies. When the firewall identifies suspicious traffic, i.e. spoofing, it knows how to continually block the entering signal and provides the organization with an exact time by using a local oscillator or an atomic clock back-up.
  • The Receiving Layer – Microsemi’s S600/ S650 models of the NTP/ PTP servers are based on GNSS receivers. This means that the servers enable reception for more than one satellite constellation (GPS, Glonass, Galileo, etc.). GNSS usage enables redundancy in satellite reception in the event of obstruction or deception in a single system.
  • The Management Layer – Microsemi developed the management software Timepictra NMS, which enables management of all elements in the synchronization network. Element management enables online data reception regarding the synchronization systems on the network, creates comparative statistics, and receives alerts if it identifies anomalies. Controlled management of the system via the Timepictra program also makes command and control of the synchronization network possible in real time and significantly decreases reaction time in the event of an immediate response.
  • The Holdover Layer – Due to increased awareness regarding obstruction, the United Nation’s International Telecommunication Union (ITU) has published strict standards for non-GPS networks over the years. The application of the G.8272.1 and G.811.1 standards via ePRTC systems can enable organizations to maintain the accuracy of 100 nanoseconds for a period of 14 days (and much longer) without being dependent on GPS by algorithms known as “autonomous time scale,” which combines atomic clocks and the unique technology of Microsemi.
  • The Network Layer – Due to increased time transfer requirements in distributed organizations, time transfer over a wire network has become necessary. The protocols of time transfer on a network were set to distribute time from the network core towards its ends. The preferred solution for a distributed network is IEEE 1588 PTP in combination with APTS (Assisted Partial Timing Support). This solution makes it possible to overcome the lack of symmetry of the network, as well as to maintain an accurate level of synchronization even in instances where GPS is not available.
  • The Client Layer – Microsemi’s Domain Time II program makes the management of synchronized end units on the network (i.e. the Client) possible. The program enables full control of all end units in the organization, including statistics and tools for comparing data and correcting errors.
Threat Awareness

The dependency of organizations on GPS-based systems forces us to be aware of the threats and dangers of spoofing and jamming, to examine scenarios which can endanger business operations, and to prepare accordingly.


Currently, there is a wide range of options to defend an organization from threats to GPS-based systems, as well as solutions to reduce and minimize damage in the event of attacks or threats.

Focus Telecom provides consulting synchronization solutions, and cyber defense for banks, security organizations, government offices, and high-tech companies.