Intelligent Hash Function Based Key-Exchange Scheme for Ocean Underwater Data Transmission

This paper presents a novel key exchange scheme based on the underwater acoustic channel that tackles the challenges posed by the uncertainty and vulnerability of the ocean environment. The proposed scheme models the channel’s uncertainty by constructing expressions for noise, multipath, and Doppler parameters and introducing the concept of underwater acoustic channel interference factors using Rényi entropy. To ensure identity authentication and initial key extraction, the scheme uses an intelligent hash function based on the twisted Edwards elliptic curve. It then employs the segmented initial key sequence to generate a segmented Toeplitz matrix, which is multiplied to generate labels through block operations, ensuring secure transmission of the initial key. The scheme enhances confidentiality through an additional hash process to generate the final security key. The scheme’s correctness, robustness, and confidentiality are confirmed using information theory, and simulation results show that it achieves a key generation rate of 631 bit/s with an upper bound of the adversary’s success rate of 4.3 × 10−23 for an initial information volume of 50,000 bits, indicating significant advantages in terms of bit and bit error rates. Overall, this paper presents a promising key exchange scheme that can mitigate the challenges posed by the underwater acoustic channel’s uncertainty and vulnerability.