ModRef 2024

The 23rd workshop on Constraint Modelling and Reformulation

September 2nd, 2024; Part of CP 2024

ModRef 2024 is the 23rd in a series of workshops on Constraint Modelling and Reformulation organized as part of CP 2024, the 30st International Conference on Principles and Practice of Constraint Programming. It will be held on September 2nd, directly preceding the CP conference.

The importance of modelling and model reformulation is widely recognised, particularly for CP but also for MIP, SAT, SMT and other kinds of general-purpose solvers. There has been significant research effort in recent years into modelling and model reformulation, such as automating techniques used by expert modellers, and developing tools and techniques to target multiple types of solvers from one model.

The purpose of ModRef is to be a forum for all kinds of work in constraint modelling, including new models or new modelling ideas for any amenable problem (whether a new application or a classic benchmark), constraint reformulation techniques to improve the performance of models when solved by general-purpose solvers, and automated modelling techniques, tools, and languages. We solicit original papers that contribute to the understanding of constraint modelling or model reformulation.

Workshop topics include:

Important Dates

Abstract Submission July 3rd, 2024
Paper Submission July 7th, 2024
Notification of acceptance/rejection July 13th, 2024
Camera ready version August 23rd, 2024
Workshop day September 2nd, 2024

Call for Papers

This year ModRef will again accept paper submissions. In addition to the presentation of research results, we especially welcome submissions of novel (ongoing) work, recent breakthroughs, future directions, and descriptions of interesting aspects of existing systems.

There are three types of paper submissions: extended abstracts (at most two pages), short papers (at most eight pages) and long papers (at most fifteen pages). References are not part of the page limit. Papers are submitted through EasyChair, as a PDF file following LIPIcs guidelines. There is no requirement for papers to be anonymised before submission.

We also accept (and encourage) non-traditional electronic submissions, such as interactive works/tool demonstrations. In this case, please contact the chairs to discuss the suitability of your submission for ModRef.

All submissions will be reviewed and those that are well-written and make a worthwhile contribution to the topic of the workshop will be accepted for publication in the workshop proceedings. The proceedings will be available electronically at CP 2024. Accepted contributions will be allowed a time slot for a presentation at the workshop. In-person presentation is preferable, but we will allow remote presentation of papers when necessary.

Invited Talk

From ModRef 2014 to ModRef 2024: Ten years of CP models for solving differential cryptanalysis problems by Christine Solnon

(slides)

Abstract: This talk will tell the 10-year story of using CP for differential cryptanalysis. The story starts at ModRef 2014, where a first CP model is introduced for computing differential characteristics for AES, the most famous symmetric cipher [1]. This first model is straightforward and it does not scale well enough to solve all instances. Improvements introduced in [2] and [3] allow CP solvers to outperform dedicated approaches and solve all instances in a few hours. Since then, similar CP models have been proposed for other symmetric ciphers (e.g., Midori [4], Skinny [5], and Rijndael [6]), and other differential cryptanalysis problems (e.g., boomerang [7,8] and rectangle attacks [9]). Finally, in [10] and [11], we introduce a generic tool for automatically generating these CP models for all word-oriented ciphers.

[1] M. Minier, C. Solnon, J. Reboul: Solving a Symmetric Key Cryptographic Problem with Constraint Programming, in ModRef 2014

[2] D. Gérault, M. Minier, C. Solnon: Constraint Programming Models for Chosen Key Differential Cryptanalysis, in CP 2016

[3] D. Gérault, P. Lafourcade, M. Minier, C. Solnon: Computing AES related-key differential characteristics with constraint programming, in AIJ 2020

[4] D Gérault, P Lafourcade: Related-key cryptanalysis of midori, in IndoCrypt 2016

[5] S. Sun, D. Gerault, P. Lafourcade, Q. Yang, Y. Todo, K. Qiao, L. Hu: Analysis of AES, SKINNY, and others with constraint programming, in IACR transactions on symmetric cryptology 2017

[6] L. Rouquette, D. Gerault, M. Minier, C Solnon: And rijndael? Automatic related-key differential analysis of rijndael, in AfricaCrypt 2022

[7] S. Delaune, P. Derbez, M. Vavrille: Catching the Fastest Boomerangs: Application to SKINNY, in IACR Transactions on Symmetric Cryptology 2020

[8] L. Rouquette, M. Minier, C. Solnon: Automatic boomerang attacks search on Rijndael, in Mathematical Cryptology 2024

[9] V. Lallemand, M. Minier, L. Rouquette: Automatic search of rectangle attacks on feistel ciphers: application to WARP, in IACR Transactions on Symmetric Cryptology 2022

[10] L. Libralesso, F. Delobel, P. Lafourcade, C. Solnon: Automatic Generation of Declarative Models for Differential Cryptanalysis, in CP 2021

[11] F. Delobel, P. Derbez, A. Gontier, L. Rouquette, C. Solnon: A CP-based Automatic Tool for Instantiating Truncated Differential Characteristics, in INDOCRYPT 2023

Accepted Papers

Schedule

Session 1 (9:00-10:30)

Session 2 (11:00-12:30)

Session 3 (14:00-15:30)

Session 4 (16:00-17:30)

Program Committee

Nysret Musliu (Chair) TU Wien
Hélène Verhaeghe (Chair) KU Leuven/UCLouvain
Özgür Akgün University of St Andrews
Ignace Bleukx KU Leuven
Jip Dekker Monash University
Emir Demirović TU Delft
Andreina Francisco Rodriguez Uppsala University
Zeynep Kiziltan University of Bologna
Lucas Kletzander TU Wien
Jimmy Lee The Chinese University of Hong Kong
Kevin Leo Monash University
Ciaran McCreesh University of Glasgow
Peter Nightingale University of York
Helmut Simonis University College Cork
Charles Thomas UCLouvain
Dimosthenis Tsouros KU Leuven
Mateu Villaret Universitat de Girona
Felix Winter TU Wien