Léo Ducas

Biography

Research

I do research on cryptology, and I am more specifically interested in theoretical and practical aspects of lattice-based cryptography.

I am involved in the design of fast algorithms for use in lattice-based cryptographic protocols, and in the design of optimized cryptographic protocols for practice. This work includes candidates Quantum-safe protocols  for the NIST standardization competition (NewHope, Frodo, Kyber, Dilithium).

I am also interested the precise security estimations of lattice problems, the fine tuning of cryptanalytic algorithm and their implementation. In particular I am very active in the development of the FPLLL lattice reduction library, so as to test in practice the latest algorithmic advances, but also to provide useful tools for prototyping new algorithms.

I have also contributed to quantum cryptanalysis of lattice-based schemes, showing that not all lattices problems are equally resistant to quantum computing.

Publications

• Debris-Alazard, T, Ducas, L, & van Woerden, W.P.J. (2022). An algorithmic reduction theory for binary codes: LLL and more. IEEE Transactions on Information Theory. doi:10.1109/TIT.2022.3143620
• Ducas, L, & van Woerden, W.P.J. (2021). NTRU Fatigue: How stretched is overstretched?. In Advances in Cryptology - ASIACRYPT (pp. 3–32). doi:10.1007/978-3-030-92068-5_1
• Ducas, L, Stevens, M.M.J, & van Woerden, W.P.J. (2021). Advanced lattice sieving on GPUs, with Tensor Cores. In Proceedings of EUROCRYPT 2021 (pp. 249–279). doi:10.1007/978-3-030-77886-6_9
• Ducas, L, & Yu, Y. (2021). Learning Strikes Again: The Case of the DRS Signature Scheme. Journal of Cryptology, 34(1). doi:10.1007/s00145-020-09366-9
• Cramer, R.J.F, Ducas, L, & Wesolowski, B.P.C. (2021). Mildly short vectors in cyclotomic ideal lattices in quantum polynomial time. Journal of the ACM, 68(2). doi:10.1145/3431725
• Ducas, L, Laarhoven, T. (Thijs), & van Woerden, W.P.J. (2020). The Randomized Slicer for CVPP: Sharper, Faster, Smaller, Batchier. In Public-Key Cryptography (pp. 3–36). doi:10.1007/978-3-030-45388-6_1
• de Boer, K, Ducas, L, & Fehr, S. (2020). On the Quantum Complexity of the Continuous Hidden Subgroup Problem. In Lecture Notes in Computer Science/Lecture Notes in Artificial Intelligence. doi:10.1007/978-3-030-45724-2_12
• de Boer, K, Ducas, L, Pellet-Mary, A, & Wesolowski, B.P.C. (2020). Random self-reducibility of ideal-svp via arakelov random walks. In Lecture Notes in Computer Science/Lecture Notes in Artificial Intelligence. doi:10.1007/978-3-030-56880-1_9
• Ducas, L, Galbraith, S, Prest, T, & Yu, Y. (2020). Integral Matrix Gram Root and Lattice Gaussian Sampling Without Floats. In Lecture Notes in Computer Science/Lecture Notes in Artificial Intelligence. doi:10.1007/978-3-030-45724-2_21
• Dachman-Soled, D, Ducas, L, Gong, H, & Rossi, M. (2020). LWE with side information: Attacks and concrete security estimation. In Lecture Notes in Computer Science/Lecture Notes in Artificial Intelligence. doi:10.1007/978-3-030-56880-1_12

Current projects with external funding

• A Reduction Theory for Codes and Lattices in Cryptography (ARTICULATE)
• PRivacy preserving pOst-quantuM systEms from advanced crypTograpHic mEchanisms Using latticeS (PROMETHEUS)

Awards

• USENIX and Facebook "Internet Defense Prize" - For Newhope, joint work with Erdem Alkim, Thomas Poppelmann, Peter Schwabe (2016)