International Association for Cryptologic Research

International Association
for Cryptologic Research

CryptoDB

Gilles Dequen

Publications

Year
Venue
Title
2021
TCHES
Time-Memory Analysis of Parallel Collision Search Algorithms 📺
Parallel versions of collision search algorithms require a significant amount of memory to store a proportion of the points computed by the pseudo-random walks. Implementations available in the literature use a hash table to store these points and allow fast memory access. We provide theoretical evidence that memory is an important factor in determining the runtime of this method. We propose to replace the traditional hash table by a simple structure, inspired by radix trees, which saves space and provides fast look-up and insertion. In the case of many-collision search algorithms, our variant has a constant-factor improved runtime. We give benchmarks that show the linear parallel performance of the attack on elliptic curves discrete logarithms and improved running times for meet-in-the-middle applications.
2014
EPRINT