The L-Band Digital Aeronautical Communication System (LDACS) aims to transform aviation communications into a quantum-safe setup, where recent proposals utilize Physical Unclonable Functions (PUFs) as an authentication mechanism and quantum-safe algorithms as a Key Encapsulation Mechanism (KEM). However, the existence of novel techniques that predict the behavior of PUFs, along with severe vulnerabilities in PostQuantum Cryptography (PQC) schemes being exploitable by attacks running on classical computing infrastructures, raises concerns about their security. In this context, the paper performs a security assessment of LDACS and the extent to which the secret quantities used during the mutual authentication between an aircraft and ground control can be disclosed. It is shown that an intelligent quantum preimage algorithm can reveal these aforementioned PUF secret quantities, which are also susceptible to sophisticated side channel attacks even on isolated workstations. In addition, information set decoding and entropy are used to evaluate the strength of the proposed KEMs for LDACS, which are also benchmarked to identify trade-offs between security and performance. Overall, our findings suggest a hardware implementation of CRYSTALS-Kyber as KEM, to further reduce latency, and the utilization of a public key infrastructure for authentication.
The L-Band Digital Aeronautical Communication System (LDACS) aims to transform aviation communications into a quantum-safe setup, where recent proposals utilize Physical Unclonable Functions (PUFs) as an authentication mechanism and quantum-safe algorithms as a Key Encapsulation Mechanism (KEM). However, the existence of novel techniques that predict the behavior of PUFs, along with severe vulnerabilities in PostQuantum Cryptography (PQC) schemes being exploitable by attacks running on classical computing infrastructures, raises concerns about their security. In this context, the paper performs a security assessment of LDACS and the extent to which the secret quantities used during the mutual authentication between an aircraft and ground control can be disclosed. It is shown that an intelligent quantum preimage algorithm can reveal these aforementioned PUF secret quantities, which are also susceptible to sophisticated side channel attacks even on isolated workstations. In addition, information set decoding and entropy are used to evaluate the strength of the proposed KEMs for LDACS, which are also benchmarked to identify trade-offs between security and performance. Overall, our findings suggest a hardware implementation of CRYSTALS-Kyber as KEM, to further reduce latency, and the utilization of a public key infrastructure for authentication.
The aviation industry faces significant challenges due to rising global air travel demand. Frequency saturation in Air Traffic Management (ATM) leads to communication problems, necessitating the enhancement of traditional systems. The Single European Sky ATM Research (SESAR) initiative, backed by the European Commission, aims to digitize ATM, with the L-band Digital Aeronautical Communications System (LDACS) as a key component. LDACS aims to improve communication, enhance surveillance, and optimize airspace usage for safer, more efficient ATM. Although LDACS is protected against most cyberattacks, a critical security objective, anonymity, is currently overlooked. To strengthen LDACS’s security, robust authentication mechanisms, Post-Quantum security, and measures to ensure aircraft anonymity are crucial. Therefore, we propose a comprehensive security framework to enhance LDACS’s cybersecurity, focusing on mutual authentication and key agreement. The protocol uses Physical Unclonable Function (PUF) for robust mutual authentication and Bit-flipping Key Encapsulation (BIKE) for secure session key establishment utilizing Post-Quantum Cryptography (PQC). This framework ensures anonymity and secure communication between aircraft and ground stations while minimizing message exchange, latency, and data overhead. An informal security analysis confirms our proposed framework’s potential to augment the efficiency and security of ATM operations.
The seamless integration of Unmanned Aerial Systems (UAS) into public airspace necessitates a robust UAV Traffic Management (UTM) system. Information security in communications plays a pivotal role in ensuring the operational safety of the UTM. Maintaining the integrity and authentication of unicast communications, such as command and video information, is imperative to thwart tampering and impersonation. Encryption emerges as an optimal solution for safeguarding such data. Efficient utilization of symmetrical encryption mandates the imple-mentation of secure key exchange mechanisms. However, intro-ducingAuthenticated Key Exchange (AKE) standards on diminutive Unmanned Aerial Vehicles (UAVs) encounters problems due to hardware limitations. To surmount this challenge, lightweight cryptographic algorithms tailored for resource-constrained hard-ware have been developed. Nonetheless, both lightweight and conventional cryptographic algorithms are susceptible to quantum computing threats. In response, post-quantum cryptographic primitives are undergoing standardization. This study assesses post-quantumKey Encapsulation Mechanism (KEM) candidates, namely CRYSTALS-Kyber, Hamming Quasi-Cyclic (HQC), and BIKE, on hardware resembling small UAVs. The evaluation of these algorithms focuses on computation time, considering real-time tasks during flights. The findings affirm the viability of employing unmodified standards on resource-constrained hardware concurrently with other priority tasks. Furthermore, quantum-vulnerable standards are also investigated to compare their performance against their more secure counterparts. All three post-quantum KEM candidates demonstrate usability in this environment, with CRYSTALS-Kyber being recommended for its superior performance, even surpassing certain prevailing standards.
Satellite communication networks play a critical role in providing connectivity to remote regions and areas with limited infrastructure. However, their inherently open nature and physical exposure make them particularly susceptible to security threats, including replay, impersonation, and man-in- the-middle attacks. The emergence of quantum computing further undermines the robustness of conventional cryptographic schemes that rely on number-theoretic assumptions. To mitigate these challenges, this article proposesHBQS, a lightweight post-quantum authentication framework designed for satellite platforms with limited resources.HBQSintegrates Physically Unclonable Functions (PUFs) with hash-based cryptography, leveraging SPHINCS+ digital signatures and SHA-3 hashing to provide secure mutual authentication and session key establishment. The protocolHBQSwas implemented and evaluated on embedded hardware platforms, including Raspberry Pi 4.0, PYNQ-Z2 FPGA, and a Dell ground control station. The experimental results demonstrate thatHBQSachieves mutual authentication in 0.88 ms, offering an approximately 67% reduction in execution time compared to representative baselines from the prior literature. Entropy analysis confirms that the proposed protocol maintains a high entropy across critical components, withHBQSachieving a signature entropy of 164.63 bits and PUF response entropy of 172.58 bits, indicating strong resistance to statistical and modeling attacks. A formal security analysis conducted within the Random Oracle Model demonstrates semantic security against both classical and quantum adversaries. The protocolHBQSshows a significant improvement over existing methods, achieving approximately 67% reduction in computational execution time, approximately 11.5% faster user-side handshake time, approximately 0.6% improvement on the satellite side and full security coverage across all evaluated security features with only a 21.4% increase in static memory usage as the trade-off. These findings positionHBQSas an efficient, secure, and scalable authentication solution for next-generation satellite communication systems operating in the post-quantum era.
In this paper, a generic post-quantum authentication protocol is constructed for quantum-resistant satellite communication. This scheme was proposed to address emerging authentication needs in post-quantum satellite communication systems consistent with evolving standards such as Consultative Committee for Space Data Systems (CCSDS) and European Telecommunications Standards Institute (ETSI). In the proposed authentication, it is aimed to obtain additional security features and low communication complexity based on simple operations and post-quantum algorithms. The mutual authentication is achieved by using Physical Unclonable Functions (PUF), Hash Message Authentication Code (HMAC), and post-quantum cryptography (PQC) primitives. The security analysis shows that the proposed authentication provides additional security properties and resistance to replay and man-in-the-middle (MitM) attacks. The main difference between the proposed protocol and PQC-based authentication for satellites in the literature is that it does not require complex operations and provides anonymity, integrity, and legitimacy with the help of lightweight principles. The proposed scheme leverages National Institute of Standards and Technology (NIST)-approved post-quantum cryptographic primitives (e.g., CRYSTALS-Kyber, HQC, SHA3-256), while the overall authentication protocol design is novel and constitutes the main contribution of our work.
The rapid digitization of aviation communication and its dependent critical operations demand secure protocols that address domain-specific security requirements within the unique functional constraints of the aviation industry. These secure protocols must provide sufficient security against current and possible future attackers, given the inherent nature of the aviation community, that is highly complex and averse to frequent upgrades as well as its high safety and cost considerations. In this work we propose a pair of quantum-secure hybrid key exchange protocols (PQAG-KEMandPQAG-SIG) to secure communication between aircrafts in-flight and ground stations.PQAG-KEMleverages post-quantum and classical Key Encapsulation Mechanisms (KEMs) to ensure the hybrid security of the protocol against classical as well as future quantum adversaries.PQAG-SIG, alternatively, uses quantum-safe digital signatures to achieve authentication security. We provide an implementation of bothPQAG-KEMandPQAG-SIG, and compare favourably with current state-of-the-art secure avionic protocols. Finally, we provide a formal analysis of our newPQAGprotocols in a strong hybrid key exchange framework.
As quantum computing advances, modern cryptographic standards face an existential threat, necessitating a transition to post-quantum cryptography (PQC). The National Institute of Standards and Technology (NIST) has selected CRYSTALS-Kyber and CRYSTALS-Dilithium as standardized PQC algorithms for secure key exchange and digital signatures, respectively. This study conducts a comprehensive performance analysis of these algorithms by benchmarking execution times across cryptographic operations such as key generation, encapsulation, decapsulation, signing, and verification. Additionally, the impact of AVX2 optimizations is evaluated to assess hardware acceleration benefits. Our findings demonstrate that Kyber and Dilithium achieve efficient execution times, outperforming classical cryptographic schemes such as RSA and ECDSA at equivalent security levels. Beyond technical performance, the real-world deployment of PQC introduces challenges in telecommunications networks, where large-scale infrastructure upgrades, interoperability with legacy systems, and regulatory constraints must be addressed. This paper examines the feasibility of PQC adoption in telecom environments, highlighting key transition challenges, security risks, and implementation strategies. Through industry case studies, we illustrate how telecom operators are integrating PQC into 5G authentication, subscriber identity protection, and secure communications. Our analysis provides insights into the computational trade-offs, deployment considerations, and standardization efforts shaping the future of quantum-safe cryptographic infrastructure.