A Cybersecurity Architecture for the L-band Digital Aeronautical Communications System (LDACS)

With air transportation growing and current civil aeronautical communication systems reaching their capacity limit in high density areas, the need for new aeronautical communication technologies becomes apparent. The biggest challenge in recent years is the transition from analogue voice to digital data communication and the related trend towards an increased autonomous data processing. A promising candidate for the digital future communication infrastructure in continental areas is the terrestrial long-range L-band Digital Aeronautical Communications System (LDACS), which is currently in the process of being standardized by the International Civil Aviation Organization (ICAO). As safety and security are strongly intertwined in civil aviation, every installation of LDACS requires protection against cyber-attacks. This paper introduces a cybersecurity architecture for LDACS and proposes suitable security algorithm, which can achieve the security objectives on top of the architecture. Therefore we integrate new security functions within the existing protocol stack of LDACS. We provide an architecture for user data encryption, data integrity, authenticated key agreement, entity authentication, broadcast channel protection, and key and access management.