Harsha, T.S.Katasani, V.S.Partani, R.Chandavarkar, B.R.2026-02-062023Springer Proceedings in Mathematics and Statistics, 2023, Vol.403, , p. 511-52221941009https://doi.org/10.1007/978-3-031-16178-0_36https://idr.nitk.ac.in/handle/123456789/29575Communication in underwater acoustic networks (UANs) is plagued by resource constraints and environmental issues. In this chapter, we present a novel key generation algorithm based on the geolocation of sender and receiver nodes and then design a lightweight, 10-round iteration block cipher algorithm for UAN communication. Using theoretical analysis, our algorithm should resist brute-force searches for adversarial attacks, such as failure of one sensor node does not affect the whole topology. In essence, it adds a second layer of security by combining geolocation with the encryption algorithm. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.Asymmetric Key CryptographyBlock cipherGeoencryptionSession-based approachUnderwater acoustic network