Yadukha, Dariya2025-04-022025-04-022024Yadukha, D. The Modification of Post-Quantum AJPS-1 Cryptosystem by Changing the Metric / Dariya Yadukha // Theoretical and Applied Cybersecurity: scientific journal. – 2024. – Vol. 6, No. 1. – P. 10-15. – Bibliogr.: 11 ref.https://ela.kpi.ua/handle/123456789/73209This paper considers the AJPS-1 post-quantum cryptosystem. A feature of this cryptosystem is the useof arithmetic modulo Mersenne number, in particular, the AJPS cryptosystem uses relations for theHamming weight of integers modulo Mersenne number. To create a modification of this cryptosystemby changing the metric, relations of the𝑂𝑆𝐷metric for integers modulo Mersenne number wereobtained. The paper describes the constructed modification of the AJPS-1 cryptosystem with a changedmetric and analyses its advantages compared to the AJPS-1 cryptosystem. This modification allows toincrease the variance of the decryption parameter, which improves the resistance of the cryptosystem tociphertext-only (known ciphertext) attacks aimed at determining the private key.enpost-quantum cryptographythe AJPS cryptosystemthe Mersenne-756839 cryptosystemHamming weightMersenne numbersArticleP. 10-15https://doi.org/10.20535/tacs.2664-29132024.1.299589003.26