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Ass.-Prof. Dr. Arnab Roy

Professor

### News

- Paper on efficient modes for algebraic hashing is accepted at IEEE CSF 2024.
- Paper on a new expanding PRF and its application is accepted at ACNS 2024.
- Paper on a new KDF and its application to Signal (like) protocol(s) is accepted at ACM ASIACCS 2024.
- I am hiring a PhD student. Our university offers a 4-year work contract with benefits and social security included. The legally binding vacancy note allows you to apply online by 5 June 2024. I
am looking forward to your application. Feel free to reach out if you have any questions.
- I serve as a PC member of CT-RSA 2024, the cryptographers’ track at the RSA conference.
- Paper on quantum cryptanalysis has been accepted by Designs, Codes and Cryptography.

### Research Interests

- Cryptography and cryptanalysis
- Secure and private computation
- Information security

### Positions

since 09/2023 |
Assistant Professor (tenure track with qualification agreement), Security and Privacy Lab, University of Innsbruck, Austria |

01/2020 – 09/2023 |
Lecturer, Cybersecurity Research Group, Alpen-Adria-Universität Klagenfurt, Austria |

09/2017 – 12/2019 |
Senior Research Associate, Cryptography Research Group, University of Bristol, UK |

06/2014 – 04/2017 |
Postdoctoral Fellow, Cybersecurity Group, Technical University of Denmark (DTU), Denmark |

2009 – 2010 |
Research Project Assistant, Indian Statistical Institute, Kolkata, India |

2007 – 2008 |
Research Engineer, Guavus Network Systems, Gurgaon, India |

2007 |
Research Intern, Microsoft Research, Bangalore, India |

### Education

2010 – 2014 |
Ph.D. in Computer Science, CryptoLUX Research Group, University of Luxembourg, Luxembourg |

2005 – 2007 |
M.Tech. in Computer Science, Indian Statistical Institute, Kolkata, India |

2002 – 2004 |
M.Sc. in Mathematics, Indian Institute of Technology (IIT), Kanpur, India |

1999 – 2002 |
B.Sc.(Hons.) in Mathematics, University of Calcutta, Kolkata, India |

### Publications

The publications are listed in reverse chronological order. More bibliographical information on them can be found on my Google scholar and DBLP pages.

- Andreeva, E., Cogliati, B., Lallemand, V., Minier, M., Purnal, A., and Roy, A. Masked Iterate-Fork-Iterate: A New Design Paradigm for Tweakable Expanding Pseudorandom Function. In
*Applied Cryptography and Network Security (ACNS)*. Lecture Notes in Computer Science 14584, Springer Nature Switzerland, 2024, pp. 433–459. [Publisher] - Hodzic, S., Andreeva, E., and Roy, A. Quantum cryptanalysis of Farfalle and (generalised) key-alternating Feistel networks.
*Designs, Codes and Cryptography*, *92*, (2023), 227–257. [Publisher] - Harmon, L., Delavignette, G., Roy, A., and Silva, D. PIE: p-adic Encoding for High-Precision Arithmetic in Homomorphic Encryption. In
*Applied Cryptography and Network Security, ACNS 2023, Proceedings, Part I*. Lecture Notes in Computer Science 13905, Springer, 2023, pp. 425–450. [Publisher] - Yan, Y., Oswald, E., and Roy, A. Not Optimal but Efficient: A Distinguisher Based on the Kruskal-Wallis Test. In
*Information Security and Cryptology - ICISC 2023 - 26th International Conference on Information Security and Cryptology, ICISC 2023, Seoul, South Korea, November 29 - December 1, 2023, Revised Selected Papers, Part I*. Lecture Notes in Computer Science 14561, Springer, 2023, pp. 240–258. [Publisher] - Andreeva, E., Bhattacharyya, R., and Roy, A. Compactness of Hashing Modes and Efficiency Beyond Merkle Tree. In
*Advances in Cryptology - EUROCRYPT 2021 - International Conference on the Theory and Applications of Cryptographic Techniques, Proceedings, Part II*. Lecture Notes in Computer Science 12697, Springer, 2021, pp. 92–123. [Publisher] - Grassi, L., Khovratovich, D., Rechberger, C., Roy, A., and Schofnegger, M. Poseidon: A New Hash Function for Zero-Knowledge Proof Systems. In
*30th USENIX Security Symposium (USENIX Security 21)*. USENIX Association, 2021, pp. 519–535. [Publisher] - Roy, A., Andreeva, E., and Sauer, J.F. Interpolation Cryptanalysis of Unbalanced Feistel Networks with Low Degree Round Functions. In
*Selected Areas in Cryptography - SAC 2020*. Lecture Notes in Computer Science 12804, Springer, 2020, pp. 273–300. [Publisher] - Andreeva, E., Lallemand, V., Purnal, A., Reyhanitabar, R., Roy, A., and Vizár, D. Forkcipher: A New Primitive for Authenticated Encryption of Very Short Messages. In
*Advances in Cryptology - ASIACRYPT 2019 - International Conference on the Theory and Application of Cryptology and Information Security, Proceedings, Part II*. Lecture Notes in Computer Science 11922, Springer, 2019, pp. 153–182. [Publisher] - Albrecht, M.R., Grassi, L., Perrin, L., et al. Feistel Structures for MPC, and More. In
*Computer Security - ESORICS 2019 - European Symposium on Research in Computer Security, 2019, Proceedings, Part II*. Lecture Notes in Computer Science 11736, Springer, 2019, pp. 151–171. [Publisher] - Gao, S., Roy, A., and Oswald, E. Constructing TI-Friendly Substitution Boxes Using Shift-Invariant Permutations. In
*Topics in Cryptology - CT-RSA 2019 - The Cryptographers’ Track at the RSA Conference 2019, Proceedings*. Lecture Notes in Computer Science 11405, Springer, 2019, pp. 433–452. [Publisher] - Green, J., Roy, A., and Oswald, E. A Systematic Study of the Impact of Graphical Models on Inference-Based Attacks on AES. In
*Smart Card Research and Advanced Applications*. Lecture Notes in Computer Science 11389, Springer, 2018, pp. 18–34. [Publisher] - Albrecht, M.R., Grassi, L., Rechberger, C., Roy, A., and Tiessen, T. MiMC: Efficient Encryption and Cryptographic Hashing with Minimal Multiplicative Complexity. In
*Advances in Cryptology - ASIACRYPT 2016 - International Conference on the Theory and Application of Cryptology and Information Security, Proceedings, Part I*. Lecture Notes in Computer Science 10031, 2016, pp. 191–219. [Publisher] - Kölbl, S. and Roy, A. A Brief Comparison of Simon and Simeck. In
*Lightweight Cryptography for Security and Privacy, LightSec 2016*. Lecture Notes in Computer Science 10098, Springer, 2016, pp. 69–88. [Publisher] - Coron, J.-S., Roy, A., and Vivek, S. Fast Evaluation of Polynomials over Binary Finite Fields and Application to Side-channel Countermeasures.
*Journal of Cryptographic Engineering*, *5*, 2 (2015), 73–83. [Publisher] - Biryukov, A., Roy, A., and Velichkov, V. Differential Analysis of Block Ciphers SIMON and SPECK. In
*Fast Software Encryption - 21st International Workshop, FSE 2014 Proceedings*. Lecture Notes in Computer Science 8540, Springer, 2014, pp. 546–570. [Publisher] - Coron, J.-S., Roy, A., and Vivek, S. Fast Evaluation of Polynomials over Binary Finite Fields and Application to Side-Channel Countermeasures. In
*Cryptographic Hardware and Embedded Systems - CHES 2014 Proceedings*. Lecture Notes in Computer Science 8731, Springer, 2014, pp. 170–187. [Publisher] - Roy, A. and Vivek, S. Analysis and Improvement of the Generic Higher-Order Masking Scheme of FSE 2012. In
*Cryptographic Hardware and Embedded Systems - CHES 2013 Proceedings*. Lecture Notes in Computer Science 8086, Springer, 2013, pp. 417–434. [Publisher] - Bhattacharyya, R. and Roy, A. Secure Message Authentication Against Related-Key Attack. In S. Moriai, ed.,
*Fast Software Encryption - FSE 2013.* Lecture Notes in Computer Science 8424, Springer, 2013, pp. 305–324. [Publisher] - Biryukov, A., Leurent, G., and Roy, A. Cryptanalysis of the "Kindle" Cipher. In
*Selected Areas in Cryptography, SAC 2012.* Lecture Notes in Computer Science 7707, Springer, 2012, pp. 86–103. [Publisher] - Leurent, G. and Roy, A. Boomerang Attacks on Hash Function Using Auxiliary Differentials. In
*Topics in Cryptology - CT-RSA 2012. Proceedings*. Lecture Notes in Computer Science 7178, Springer, 2012, pp. 215–230. [Publisher] - Biryukov, A., Nikolic, I., and Roy, A. Boomerang Attacks on BLAKE-32. In
*Fast Software Encryption - 18th International Workshop, FSE 2011.* Lecture Notes in Computer Science 6733, Springer, 2011, pp. 218–237. [Publisher]

### Professional Activities

##### Program committees

SCN (2022), CT-RSA (2022, 2024), Indocrypt (2020), PKC (2020), FSE (ToSC) (2019)

##### External reviewer

Asiacrypt (2021, 2020, 2018, 2012), FSE (2020, 2016, 2013, 2012), Eurocrypt (2019, 2015), Crypto (2018, 2011), ACNS (2017, 2014), CT-RSA 2015, CHES 2013

##### Organizer

[ALPSY workshop] (https://alpsy-informatik.uibk.ac.at) (2024)
SILC workshop (co-located with Eurocrypt 2021)