Digital communication has expanded exponentially, thereby increasing the level of protection required for textual data, necessitating a formidable encryption algorithm that can withstand advanced attacks. Our methodology introduces a new text encryption algorithm selected via a two-dimensional (2D) logistic map that leverages chaotic dynamics to provide high security. The 2D logistic map, as adapted and implemented in our proposed framework, is combined with coupling terms and perturbations in order to produce highly unpredictable chaotic sequences. The encryption algorithm is a two-stage algorithm: permutation of the positions of the characters based on a chaotic sequence and substitution based on dynamically generated key streams. The high sensitivity of key (diffusionrate > 99.5%), high randomness in the output of cipher texts ( entropy ≥ 7.98 ), and high resistance to frequency analysis attacks are shown by extensive security analysis. A comparative analysis with the classical ciphers, such as Caesar, AE,S and stream ciphers, indicates better performance in relation to security measures and computation speed. The algorithm has a time complexity of O(n) and cryptographic strength that is appropriate for use in realtime applications. The algorithm proves its usefulness in the security of textual communications as experimental results confirm, with possible extrapolations of the algorithm to the IoT messaging systems and the hybrid multimedia encryption

Chaos,2D logistic map, cryptography, chaotic systems, nonlinear dynamics, information security