A Dual-Key Based RSA Cryptosystem

Authors: Vasudeo Patil, Arpit Vijay Raikwar

Abstract: Rivest–Shamir–Adleman (RSA) is a widely used public-key cryptosystem based on a single public-private key pair. This paper proposes a dual-key RSA cryptosystem that employs two public keys with their corresponding private keys, introducing additional key dependency into the encryption and decryption processes. The correctness of the proposed scheme is established through a formal mathematical proof and illustrated with a numerical example. The proposed scheme and conventional RSA are implemented in Java using Apache NetBeans IDE 25, and their computational performance is evaluated under identical parameters. The experimental results indicate that the proposed scheme achieves performance comparable to conventional RSA. The security analysis using ProVerif verifies message and private-key secrecy under a symbolic adversarial model. The proposed dual-key RSA cryptosystem represents a structured and efficient extension of the classical RSA scheme suitable for academic and experimental cryptographic studies.

DOI: http://doi.org/10.5281/zenodo.21914877