Communication in an underwater environment presents many challenges, due to its unique characteristics of throughput, delay, and error rates. The acoustic channels commonly used for underwater communication have inherent broadcast characteristics and require non-trivial solutions to achieve secure and authenticated communications. The complexity of security challenges is further increased by the ongoing transition to quantum-resistant cryptography. Our paper discusses post-quantum cryptographic solutions for underwater broadcast communication scenarios. Specifically, we present and analyze solutions for sender authentication and key management based on private key cryptography and discuss perfect forward secrecy of communication keys, taking into consideration the constraints of the underwater environment.
Communication in an underwater environment presents many challenges, due to its unique characteristics of throughput, delay, and error rates. The acoustic channels commonly used for underwater communication have inherent broadcast characteristics and require non-trivial solutions to achieve secure and authenticated communications. The complexity of security challenges is further increased by the ongoing transition to quantum-resistant cryptography. Our paper discusses post-quantum cryptographic solutions for underwater broadcast communication scenarios. Specifically, we present and analyze solutions for sender authentication and key management based on private key cryptography and discuss perfect forward secrecy of communication keys, taking into consideration the constraints of the underwater environment.
Underwater communication, with its unique characteristics of throughput, delay, error rates, and communicating nodes, often constrained by battery power, presents a significant challenge. In the face of a quantum threat to cryptography, the need to correctly choose quantum-safe cryptographic schemes and key management protocols capable of meeting underwater communication constraints has become crucial. Our paper addresses the topic of securing underwater communication, and more generally, the topic of securing a constrained network. It analyses available post-quantum cryptographic solutions and assesses their applicability to underwater information exchange.
This paper focuses on defining specific scenarios for quantum-safe underwater communication to drive security requirements. The maritime environment in general and the underwater domain in particular have unique constraints and require the use of specialized cryptographic techniques. The two scenarios presented are underwater harbor protection and anti-submarine warfare. Employing post-quantum cryptographic algorithms in these use cases enhances security and maintains the integrity of sensor data. This research contributes to strengthening underwater communication security through advancements in acoustic cryptography, error correction codes, adaptive modulation, and energy-efficient algorithms.
Secure underwater communication is vital for maritime operations; however, acoustic channels pose significant challenges, including limited bandwidth, high latency, and complex propagation effects. With quantum computing threatening classical methods, there is a need for cryptographic schemes that can withstand quantum attacks. This study presents a quantum-resistant underwater communication system that integrates CRYSTALS-Kyber for key encapsulation, SPHINCS+ for digital signature authentication, and AES for efficient payload encryption. The proposed system is evaluated under realistic underwater channel simulations that account for propagation delay, multipath fading, and Doppler effects. Experimental benchmarks reveal that while post-quantum operations, such as CRYSTALS-Kyber key encapsulation (2.41-4.91ms) and SPHINCS+ signing (96.10ms) exhibit higher latencies compared to classical ECC/ECDSA methods, these latencies remain within acceptable limits given the substantial security advantages they offer. This approach bridges the gap between rigorous quantum-resistant security and practical underwater deployment, establishing a robust foundation for future enhancements in error correction and adaptive network strategies.
Security is a crucial aspect of underwater acoustic networks, that are often used in mission critical scenarios, such as coastal surveillance, rapid environmental assessment and mine countermeasure applications. The broadcast nature of the acoustic channel makes it vulnerable to a variety of attacks, such as spoofing, men-in-the-middle and jamming. Moreover, the lack of a standardized key distribution system makes data confidentiality challenging. In this paper we investigate the use of quantum key distribution (QKD) in underwater networks, in order to ensure confidentiality and integrity of the communication. While in the terrestrial domain the use of the one-time-pad protocol (requiring the key length to be equal to the message length) is limited by the low rate of the QKD rate compared to the bitrate of radio transmissions, in the underwater domain the limited bandwidth of the acoustic channel makes QKD a valid approach also for the one-time-pad protocol. The system is tested both with an emulator and a field test: results show that QKD can be a valuable system to secure underwater acoustic networks.
The growing importance of Underwater Networks (UNs) in mission-critical activities at sea enforces the need for secure Underwater Communications (UCs). Classical encryption techniques can be used to achieve secure data exchange in UNs. However, the advent of Quantum Computing will pose threats to classical cryptography, thus challenging also UCs. Currently, underwater crypto-systems mostly adopt symmetric ciphers, which are considered computationally quantum-robust, but pose the challenge of distributing the secret key upfront. Post-Quantum Public-Key (PQPK) protocols promise to overcome the key distribution problem. The security of PQPK protocols, however, only relies on the assumed computational complexity of some underlying mathematical problems. Moreover, the use of resource hungry PQPK algorithms in resource-constrained environments such as UNs can require non-trivial hardware/software optimization efforts. An alternative approach is underwater Quantum Key Distribution (QKD), which promises unconditional security built upon the physical principles of Quantum Mechanics. This tutorial provides a basic introduction to free-space Underwater QKD (UQKD). At first, the basic concepts of QKD are presented, based on a fully worked out QKD example. A thorough state-of-the-art analysis of UQKD is carried out. The paper subsequently provides a theoretical analysis of the QKD performance through free-space underwater channels, and its dependence on the key optical parameters of the system and seawater. Finally, open challenges, points of strength and perspectives of UQKD are identified and discussed.
The growing importance of Underwater Networks (UNs) in mission-critical activities at sea enforces the need for secure Underwater Communications (UCs). Classical encryption techniques can be used to achieve secure data exchange in UNs. However, the advent of Quantum Computing will pose threats to classical cryptography, thus challenging also UCs. Currently, underwater crypto-systems mostly adopt symmetric ciphers, which are considered computationally quantum-robust, but pose the challenge of distributing the secret key upfront. Post-Quantum Public-Key (PQPK) protocols promise to overcome the key distribution problem. The security of PQPK protocols, however, only relies on the assumed computational complexity of some underlying mathematical problems. Moreover, the use of resource hungry PQPK algorithms in resource-constrained environments such as UNs can require non-trivial hardware/software optimization efforts. An alternative approach is underwater Quantum Key Distribution (QKD), which promises unconditional security built upon the physical principles of Quantum Mechanics. This tutorial provides a basic introduction to free-space Underwater QKD (UQKD). At first, the basic concepts of QKD are presented, based on a fully worked out QKD example. A thorough state-of-the-art analysis of UQKD is carried out. The paper subsequently provides a theoretical analysis of the QKD performance through free-space underwater channels, and its dependence on the key optical parameters of the system and seawater. Finally, open challenges, points of strength and perspectives of UQKD are identified and discussed.