Elliptic Curve Cryptography Reimagined: Post-Quantum Resilience Through Isogeny Graphs
PAULO SÉRGIO DE ANDRADE
The impending arrival of large-scale quantum computers poses a significant threat to modern public-key cryptography, which is largely based on the hardness of integer factorization and the discrete logarithm problem. Elliptic Curve Cryptography (ECC), a cornerstone of current digital security, is particularly vulnerable to attacks by quantum algorithms, notably Shor's algorithm. This has catalyzed the development of Post-Quantum Cryptography (PQC), a new generation of cryptographic systems designed to be secure against both classical and quantum adversaries. Among the various PQC families, isogeny-based cryptography has emerged as a compelling, albeit complex, candidate. This paper explores the reimagination of elliptic curve principles for a post-quantum world through the lens of isogeny graphs. We provide a comprehensive overview of the transition from classical ECC to isogeny-based schemes, detailing the mathematical foundations of elliptic curve isogenies and the construction of supersingular isogeny graphs. The core of our analysis focuses on how the problem of finding a secret isogeny path between two curves in this graph forms the basis for quantum-resistant cryptographic protocols. We review the evolution of seminal protocols such as Supersingular Isogeny Diffie-Hellman (SIDH) and its variants, discussing their initial promise. Crucially, the paper also addresses the recent groundbreaking cryptanalytic attacks on SIDH, which have reshaped the landscape of isogeny-based cryptography. We analyze the implications of these attacks and the ongoing research to develop new, more secure isogeny-based schemes like SQISign. By comparing the performance metrics (key size, performance, security) of isogeny-based systems with other leading PQC candidates, such as those based on lattices and codes, this paper offers a balanced perspective on their potential role in future cryptographic standards.
•Nov 19, 2025•0 citations