Security in Global Navigation Satellite Systems: authentication, integrity protection and access control

In the last decades the use of Global Navigation Satellite System (GNSS) positioning has spread through numerous commercial applications and permeated our daily life. Matching this growing interest for precise positioning worldwide, new systems have been designed and deployed, such as Galileo, the European GNSS. As these systems are relied upon in an ever growing number of safety critical applications, it is vital to devise protections and countermeasures against any threats that may target GNSS modules to harm underlying service. The potential economical advantage that derives from disrupting or manipulating the service is indeed an incentive for malicious users to devise smarter and more sophisticated threats. This thesis tackles the evolution of attacks and corresponding security measures in GNSS, investigating state-of-the-art approaches from both the attacker’s and the system’s point of view. The work focuses on various security targets, such as authentication, integrity protection and access control, exploring threats and solutions at both signal and data level. Securing GNSS from malicious entities indeed requires protecting all of its components: the navigation message, the signal-in-space and the computed Position, Velocity and Time (PVT). All three domains are investigated with the aim of assessing the vulnerability of the system to state-of-the-art threats and providing guidelines for the addition of future security features.