Spoofing at Sea


In a world where ‘traditional’ navigation plays a secondary role to electronic navigation, the importance of ensuring an accurate GPS position has never been more important.

Cyber security has been a hot-topic for several years now, but the number of incidents of reported GPS interference or ‘spoofing’ is increasing.  

Christopher Loizou, VP Maritime of Orolia Maritime discusses both how important it is to ensure your vessels’ navigation systems are provided with accurate data and how to protect a vessel from navigating with an unreliable GPS position.

Ensuring Navigational Safety: GNSS Resilience

Since the development of the Global Navigation Satellite System (GNSS) over 40 years ago, position, navigation and timing (PNT) based on satellite input has been vital to many critical systems on board vessels, allowing a very precise determination of location. The maritime industry relies on trustworthy PNT in transport infrastructure, navigation, communications, search and rescue applications, fishing operations and regulation, using a variety of available satellite constellations such as GPS, Galileo, Glonass, Beidou etc.

Cyber-attacks can come in many guises, acting as a route for fraudsters to forge invoices, install ransomware or alter cargo manifests to hide illicit goods. As the threats become more sophisticated, poor cyber security could compromise commercial vessels’ safety through interference with navigation accuracy.

As the 2021 deadline for the IMO’s ‘Maritime Cyber Risk Management in Safety Management Systems’ mandate draws nearer, it is all the more important that the entire vessel management ecosystem, from port operations to critical bridge systems, includes protection of navigation by creating a resilient PNT threat detection and mitigation plan.

The value of GNSS

UK Government research in 2017 identified that a five-day loss of GNSS would cost the UK maritime economy over a billion pounds. This highlighted the growing realisation that GNSS as a source of PNT needs to be both protected and irrefutable, leading to the concept of Resilient PNT as a tool to support navigational cyber security.

GNSS signals are the primary PNT reference sources used in navigation, but their signals are very weak when they reach the Earth’s surface. They have well-known vulnerabilities and limitations that require protection and mitigation. They can be disrupted by unintentional interference and the unencrypted signal in civilian use is susceptible to attack.

Intentional interference can be the denial of access to satellite signals or ‘jamming’, so your vessel cannot determine its exact location. Spoofing, also known as advanced jamming, is the creation of additional signals that provide misleading PNT information, so the vessel’s position or time reference is no longer accurate.

Resilient PNT

Deploying traditional procedures for loss of GNSS (GPS) is not sufficient for threats such as spoofing. An unsecure navigation system would not know its positioning source has been compromised. With the advent of ECDIS and widespread use of GNSS-dependent chart plotters, the risk is accentuated.

The use of Resilient PNT for navigation cyber security, is the meeting of traditional positioning, navigation and timing technology with non-traditional and emerging technology. Navigation resilience improves the reliability, performance and safety of mission-critical applications, where discrepancy in data accuracy, availability and stability can impact the safety, security and economic viability of vessels at sea.

Navigation Protection Devices (NPDs), such as Orolia Maritime’s M-SecureSync include a monitoring component, which filters and analyses the received GNSS signals and provides an alert on the bridge if direct interference, jamming or spoofing is detected. M-SecureSync offers an additional optional layer of navigation cyber security in the event of interference with GNSS, by switching to an alternative navigation signal – Satellite Time and Location (STL).

STL is available worldwide, operating on the Iridium satellites and provides an encrypted signal 1,000 times stronger than GNSS and resists jamming and spoofing. As the NPD is independent of the vessel’s navigation system it can provide a real time indication of alerts and positional discrepancies.

There is now a growing awareness of the vulnerabilities in GNSS but what is not yet clear is what to do about them. There is no silver bullet – no one solution that can overcome the problems – but Orolia Maritime believe a combination of several alternative methods can augment GNSS and provide the resilience necessary for all critical navigation operations.


Author: Rod Maclennan 
Loss Prevention Executive