Ludovic Perret

Research and Transfer Activities

I am associate professor at Sorbonne University (SU) in the project-team POLSYS which is common between LIP6 and INRIA Paris. My research area is at the intersection of cryptography and computer algebra. I am interested by evaluating the security of cryptographic primitives by means of algebraic methods. The idea is to model a cryptographic primitive as a system of algebraic equations. This general approach is called algebraic cryptanalysis. Once this modeling is done, the problem is then to solve an algebraic system. Gröbner bases is a classical technic to do so. In POLSYS, we have applied this approach to evaluate the hardness of various problems underlying the security of most quantum-resistant algorithms : multivariate schemes, code-based as well as lattice-based schemes. It apperas that algebraic cryptanalysis an important tool for evaluating the security of quantum-resistant algorithms. I defended my habilitation thesis on these topics.
I am teaching cryptography in the master SFPN and post-quantum cryptocgraphy in a specific course at MPRI.
A large part of my activity is now devoted to industrial transfer of quantum-safe cryptography : external scientific advisor for Kryptnostic, work-package leader of RISQ the largest (so far) industrial project on quantum-safe cryptography, co-chair of CSA quantum-safe security working group and member of the quantum-safe cryptography specification group of the European Telecommunications Standards Institute (ETSI).
I am currenty involved in the creation of a new spin-off : Post-Quantum Advanced Technologies (PQAT). This spin-off was maturated in the project HFEBOOST where we developped an Android application which allows to encrypt and decrypt documents with in-house post-quantum cryptosystems.

News

• IHP thematic trimester on POST-QUANTUM ALGEBRAIC CRYPTOGRAPHY, September-December, 2021, Paris
• Quantum-Safe Cryptography for Industry (QSCI'18), August 18th, 2018, Santa-Barbara - USA
• Le grand défi du post-quantique, Hors-série de MISC sur la cryptogaphie
• "Preliminary Plan for the Standardization of Quantum-Resistant Algorithms'', public announcement of NIST at PQC16
• Post-Quantum rush officially started
• NIST Workshop on Cybersecurity in a Post-Quantum World, April 2 - 3, 2015, Maryland, USA
• COST Action Cryptanalysis of Ubiquitous Computing Systems (CRYPTACUS)
• COST Action Cryptography for Secure Digital Interaction

Some Selected Talks

• ``Gröbner Bases Techniques in Post-Quantum Cryptography", Winter School of PQC'16, February, 22 - 23, 2016, Fukuoka, Japan
• ``Algebraic Algorithms for LWE", The Mathematics of Modern Cryptography, Jul. 6 - Jul. 10, 2015, Simons Institue, Berkeley, USA
• ``Gröbner Bases Techniques in Post-Quantum Cryptography'', NIST Workshop on Cybersecurity in a Post-Quantum World, April 2 - 3, 2015, Maryland, USA

Selected Publications

The full list of publications is here and my CV is here.

• J.-C. Faugère, A. Otmani, L. Perret, F. De Portzamparc, and J.-P. Tillich, “Structural Cryptanalysis of McEliece Schemes with Compact Keys”. DCC, 2015.
• J.-C. Faugère, V. Gauthier-Umana, A. Otmani, L. Perret, and Jean-Pierre Tillich,“ A Distinguisher for High Rate McEliece Cryptosystems”. IEEE IT, 2013.
• L. Bettale, J.-C. Faugère and L. Perret, “Cryptanalysis of HFE, Multi-HFE and Variants for Odd and Even Characteristic”. Des. Codes Cryptography, 2013.
• J.-C. Faugère, A. Otmani, L. Perret and J.-P. Tillich, “Algebraic Cryptanalysis of McEliece Variants with Compact Keys”. Eurocrypt 2010.
• J.-C. Faugère, J. von zur Gathen and L. Perret, “Decomposition of Generic Multivariate Polynomials”. ISSAC'10.
• L. Bettale, J.-C. Faugère and L. Perret, “Hybrid Approach for Solving Multivariate Systems over Finite Fields”. Journal of Mathematical Cryptology, 2010.
• J.-C. Faugère, F. Levy-dit-Vehel and L. Perret, “Cryptanalysis of Minrank”. CRYPTO 2008.
• M. Sugita, M. Kawazoe, L. Perret and H. Imai, “Algebraic Cryptanalysis of 58-Round SHA-1”. FSE 2007.
• J.-C. Faugère and L. Perret, “ Cryptanalysis of 2R- Schemes”. CRYPTO 2006.
• J.-C. Faugère and L. Perret, “Polynomial Equivalence Problems: Algorithmic and Theoretical Aspects”. Eurocrypt 2006.
• L. Perret, “A Fast Cryptanalysis of the Isomorphism of Polynomials with One Secret Problem”. EUROCRYPT 2005.

PhD Students

• Luk Bettale (2008 - 2011), Algebraic Cryptanalysis of Multivariate Schemes and Hash Functions, co-supervised with J.-C. Faugère
• Frédéric Urvoy de Portzamparc (2012 -- 2015) Physical and Algebraic Analysis of Code-based Schemes, co-supervised with J.-C. Faugère

Programme Committee

• PQCrypto 2019, 10th Conference International Conference on Post-Quantum Cryptography, Chongqing, China
• SAC 2018, 25th Conference on Selected Areas in Cryptography, Alberta, Canada
• PKC 2017, 20th International Conference on Practice and Theory in Public-Key Cryptography, Amsterdam, Holland
• ISSAC 2016, 41th International Symposium on Symbolic and Algebraic Computation, Wilfrid Laurier University, Waterloo, Ontario, Canada, July 20-22 2016.
• PASCO 2015, 7th International Workshop on Parallel Symbolic Computation, University of Bath, UK, July 10-12,2015
• EuroCrypt 14, 33rd Annual International Conference on the Theory and Applications of Cryptographic Techniques, 11 - 15 May 2014, Copenhagen, Denmark
• Inscrypt 2013, 9th China International Conference on Information Security and Cryptology, Nov. 27 - Nov. 30, 2013, Guangzhou, China
• PKC 2013, 16th International Conference on Practice and Theory in Public-Key Cryptography, February 26 - March 1, Nara, Japan
• SCC 2012, 3nd International Conference on Symbolic Computation and Cryptography, 11 - 13 July 2012, Castro Urdiales, Spain
• YACC 2010, Yet Another Conference on Cryptography, 4 - 8 October, 2010, Porquerolles Island, France
• TOOLS 2010, Workshop on Tools for Cryptanalysis 2010, 22 - 23 June 2010, Royal Holloway, University of London, Egham, (UK)
• SCC 2010, 2nd International Conference on Symbolic Computation and Cryptography, 23-25 June 2010, Royal Holloway, University of London, Egham, (UK)
• Inscrypt 2010, 6th China International Conference on Information Security and Cryptology, 20-24 October 2010, Shanghai, China
• Inscrypt 2008, 4th China International Conference on Information Security and Cryptology, 14-17 December 2010, Beijing, China
• SCC 2008, First International Conference on Symbolic Computation and Cryptography, 28-30 April 2008, Beijing, China

Editorial Activity

• Editorial Board, Designs, Codes and Cryptography
• Guest Editor, Journal of Symbolic Computation, special issue "Mathematical and Computer Algebra Techniques in Cryptology"
• Guest Editor, Mathematics in Computer Science, special issue ``Symbolic Computation and Cryptography"
• Guest Editor, Journal of Symbolic Computation, special issue ``Gröbner Bases Techniques in Cryptography and Coding Theory"
• Guest Editor, RISC book series (Springer, Heidelberg), ``Gröbner Bases, Coding, and Cryptography''