Julien Devevey's Homepage
About me
I am a cryptography expert at ANSSI, the French cybersecurity agency.
Before that, I was a PhD student at École Normale Supérieure de Lyon under the supervision of
Damien Stehlé and a member of the AriC team at the LIP laboratory.
I am mainly interested in lattice-based cryptography, in particular everything about lattice-based Fiat-Shamir signatures: efficient implementations, optimisations and applications to advanced protocols.
Since 2022, I am participating in the HAETAE project, a signature submission to the Korean post-quantum Competition. We also submitted it to the 4th round of NIST PQC.
Contact: [firstname] dot [lastname] at ssi dot gouv dot fr
Publications
2023
- G+G: A Fiat-Shamir Lattice Signature Based on Convolved Gaussians [pdf] [slides] [video]
with Alain Passelègue and Damien Stehlé.
Advances in Cryptology — ASIACRYPT 2023. ASIACRYPT 2023. Lecture Notes in Computer Science, vol 14444. Springer, Cham. https://doi.org/10.1007/978-981-99-8739-9_2 - HAETAE: Shorter Lattice-Based Fiat-Shamir Signatures [pdf] [slides] [video]
with Jung Hee Cheon, Hyeongmin Choe, Tim Güneysu, Dongyeon Hong, Markus Krausz, Georg Land, Marc Möller, Damien Stehlé and Minjune Yi.
Submission Specification and preprint. - A Detailed Analysis of Fiat-Shamir with Aborts [pdf] [slides] [video]
with Pouria Fallahpour, Alain Passelègue and Damien Stehlé.
Advances in Cryptology — CRYPTO 2023. CRYPTO 2023. Lecture Notes in Computer Science, vol 14085. Springer, Cham. https://doi.org/10.1007/978-3-031-38554-4_11
2022
- On Rejection Sampling in Lyubashevsky's Signature Scheme [pdf] [slides] [video]
with Omar Fawzi, Alain Passelègue and Damien Stehlé.
Advances in Cryptology — ASIACRYPT 2022. ASIACRYPT 2022. Lecture Notes in Computer Science, vol 13794. Springer, Cham. https://doi.org/10.1007/978-3-031-22972-5_2 - Rational Modular Encoding in the DCR Setting: Non-Interactive Range Proofs and Paillier-Based Naor-Yung in the Standard Model | [pdf] [slides] [video]
with Benoît Libert and Thomas Peters.
Public-Key Cryptography — PKC 2022. PKC 2022. Lecture Notes in Computer Science, vol 13177. Springer, Cham. https://doi.org/10.1007/978-3-030-97121-2_22
2021
- Non-Interactive CCA2-Secure Threshold Cryptosystems: Achieving Adaptive Security in the Standard Model Without Pairings | [pdf] [slides] [video]
with Benoît Libert, Khoa Nguyen, Thomas Peters and Moti Yung.
Public-Key Cryptography — PKC 2021. PKC 2021. Lecture Notes in Computer Science, vol 12710. Springer, Cham. https://doi.org/10.1007/978-3-030-75245-3_24
- On the Integer Polynomial Learning with Errors Problem | [pdf] [slides] [video]
with Amin Sakzad, Damien Stehlé and Ron Steinfeld.
Public-Key Cryptography — PKC 2021. PKC 2021. Lecture Notes in Computer Science, vol 12710. Springer, Cham. https://doi.org/10.1007/978-3-030-75245-3_8
Talks
2024
- HAETAE: Short Fiat-Shamir with Aborts Signature | [slides]
Séminaire de Cryptographie — Rennes.
2023
- G+G: A Fiat-Shamir Lattice Signature Based on Convolved Gaussians | [slides]
Journées Codage et Cryptographie — Najac. - Lattice-based Signature Schemes in the Fiat-Shamir Paradigm | [slides]
PhD Defense — ENS de Lyon. - HAETAE: Shorter Fiat-Shamir with Aborts Signatures | [slides] [video]
2nd Post-Quantum Cryptography Summit — Oxford.
2022
- On Rejection Sampling in Lyubashevsky's Signature Scheme | [slides]
Séminaire de Cryptographie — Rennes. - On Rejection Sampling in Lyubashevsky's Signature Scheme | [slides]
Journées Codage et Cryptographie — Hendaye.
2021
- Non-Interactive CCA2-Secure Threshold Cryptosystems: Achieving Adaptive Security in the Standard Model Without Pairings | [slides]
IMDEA Crypto Reading Group — Virtual.
Teaching
- 2022-2023 Teaching assistant, Préparation à l'agrégation d'informatique, ENS de Lyon. Entraînement à l'épreuve de leçon.
- 2022-2023 Teaching assistant, LIFSE: Systems, Université Lyon I (Bachelor 2), with Nicolas Louvet.
- 2021-2022 Teaching assistant, LIFASR5: Systems, Université Lyon I (Bachelor 2), with Nicolas Louvet.
- 2021-2022 Teaching assistant, Computer Algebra, ENS de Lyon (Master 1), with Bruno Salvy.
- 2021-2022 Teaching assistant, Cryptography and Security, ENS de Lyon (Master 1), with Alain Passelègue.
- 2020-2021 Teaching assistant, Computer Algebra, ENS de Lyon (Master 1), with Pascal Koiran.
- 2020-2021 Teaching assistant, Cryptography and Security, ENS de Lyon (Master 1), with Damien Stehlé.