Paper 2022/357
An Effective Lower Bound on the Number of Orientable Supersingular Elliptic Curves
Abstract
In this article, we prove a generic lower bound on the number of $\mathfrak{O}$-orientable supersingular curves over $\mathbb{F}_{p^2}$, i.e curves that admit an embedding of the quadratic order $\mathfrak{O}$ inside their endomorphism ring. Prior to this work, the only known effective lower-bound is restricted to small discriminants. Our main result targets the case of fundamental discriminants and we derive a generic bound using the expansion properties of the supersingular isogeny graphs. Our work is motivated by isogeny-based cryptography and the increasing number of protocols based on $\mathfrak{O}$-oriented curves. In particular, our lower bound provides a complexity estimate for the brute-force attack against the new $\mathfrak{O}$-uber isogeny problem introduced by De Feo, Delpech de Saint Guilhem, Fouotsa, Kutas, Leroux, Petit, Silva and Wesolowski in their recent article on the SETA encryption scheme.
Metadata
- Available format(s)
-
PDF
- Category
- Public-key cryptography
- Publication info
- Published elsewhere. SAC 2022
- Keywords
- isogeny based cryptography quaternion orders quadratic orders
- Contact author(s)
- antonin leroux @ polytechnique org
- History
- 2022-09-13: last of 3 revisions
- 2022-03-18: received
- See all versions
- Short URL
- https://ia.cr/2022/357
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2022/357,
author = {Antonin Leroux},
title = {An Effective Lower Bound on the Number of Orientable Supersingular Elliptic Curves},
howpublished = {Cryptology {ePrint} Archive, Paper 2022/357},
year = {2022},
url = {https://eprint.iacr.org/2022/357}
}
