An Algorithmic Approach to (2,2)-isogenies in the Theta Model and Applications to Isogeny-based Cryptography

ePrint Report: An Algorithmic Approach to (2,2)-isogenies in the Theta Model and Applications to Isogeny-based Cryptography

Pierrick Dartois, Luciano Maino, Giacomo Pope, Damien Robert

In this paper, we describe an algorithm to compute chains of $(2,2)$-isogenies between products of elliptic curves in the theta model. The description of the algorithm is split into various subroutines to allow for a precise field operation counting.


We present a constant time implementation of our algorithm in Rust and an alternative implementation in SageMath. …

algorithm applications compute cryptography elliptic eprint report pope products report robert theta