Module-LWE Cryptosystems: A Post-Quantum RSA Replacement with Tightly Reduced Hardness
Revista, Zen, MATH, 10
The imminent threat posed by cryptographically relevant quantum computers necessitates a paradigm shift in public-key cryptography. Traditional schemes like RSA and Elliptic Curve Cryptography (ECC), the bedrock of modern secure communication, are vulnerable to quantum algorithms such as Shor's. This paper explores Module-LWE (Learning With Errors) cryptosystems as a compelling post-quantum replacement for RSA. We delve into the foundational mathematical properties of Module-LWE, highlighting its security rooted in the presumed intractability of hard lattice problems. A key focus is the concept of "tightly reduced hardness," which signifies that the security of a cryptographic scheme based on Module-LWE can be directly and efficiently linked to the worst-case hardness of an underlying lattice problem. This tight reduction allows for more aggressive parameter choices, leading to improved efficiency, smaller key and ciphertext sizes, and enhanced performance compared to generic LWE or other post-quantum candidates, without compromising security. We analyze the advantages of Module-LWE in terms of provable security, performance characteristics, and its suitability for key encapsulation mechanisms and digital signatures. The discussion encompasses its practical implications, implementation considerations, and its strong position within the NIST Post-Quantum Cryptography standardization effort, ultimately presenting Module-LWE as a robust, efficient, and future-proof alternative to RSA in a post-quantum world.
•Dec 3, 2025•0 citations