March 13, 2025, 10:00 am +Zoom (click here)
Speaker: Dipayan Das, Ph.D., Florida Atlantic University
Title: Cryptanalysis of some Lattice-based Assumptions
Abstract: Cryptography relies on the assumptions of computationally hard problems. It should be hard for security, offer functionalities for cryptographic applications, and be efficient to implement. Recently, lattice-based assumptions have emerged as a strong building block for post-quantum cryptography. In this talk, I will present recent cryptanalytic results on two lattice-based assumptions, namely the Finite Field Isomorpshim problem (PKC'18, JoMC'20), and the Partial Vandermonde Knapsack Problem (ACNS'14, DCC'15, ACISP'18, Eprint'20,DCC'22). These assumptions have been used extensively for various lattice-based constructions, including encryptions, fully homomorphic encryptions, signatures, signature aggregations, etc.
Bio: Dipayan Das is an Assistant Professor in the Florida Atlantic University Department of Mathematics and Statistics. Previously, he was a Postdoc researcher at the NTT Social Informatics Laboratories in Japan. Before that, he was a PostDoc researcher at CISPA Helmholtz center for information security in Germany. He did his PhD at the National Institute of Technology, Durgapur in India.
February 27, 2025, 10:00 am +Zoom (click here)
Speaker: Dominic Gold (Johns Hopkins University Applied Physics Laboratory) FLYER
Title: Deterministic Random Bit Generators in Cryptography
Abstract: Side-channel attacks (SCA) present a serious threat to cryptographic implementations, including those designed for post-quantum security. This talk introduces the first Correlation Power Analysis (CPA) attack on an industry-grade hardware implementation of ML-DSA within a Silicon Root of Trust framework. Our attack exploits side-channel leakage from the modular reduction process following the Number Theoretic Transform-based polynomial multiplication. By leveraging leakage from a unique reduction algorithm and the zeroization mechanism used for securely erasing sensitive data, we demonstrate secret key extraction using only 10,000 power traces. This attack compromises the integrity of the root of trust, enabling signature forgery for certificate generation. Our findings highlight critical vulnerabilities in commercially deployed post-quantum cryptographic systems and emphasize the need for robust countermeasures.
February 13, 2025, 10:00 am +Zoom (click here)
Speaker: Ivana Trummová, Ph.D. candidate, Czech Technical University (CTU) in Prague, Czech Republic FLYER
Title: Human Factors in Cryptography
Abstract: Cryptography can be considered a part of mathematics or computer science, therefore an exact and technical field. On the other hand, cryptography is created, implemented and used by people, who have to collaborate, communicate, and are prone to making mistakes. In my work, I am researching the non-technical aspects of cryptography that affect security. In one of my previous projects we have mapped the cryptography ecosystem, described the systemic barriers that hinder cryptography adoption. In another interview study, we found out how developers implement cryptographic standards and how an ideal standard specification should look like. Now I am studying the processes of cryptography competitions and their impacts on cryptographic community.
Speaker Bio: Ivana Trummová is a cryptography researcher and a teacher focusing on human factors in security and inter-disciplinary research. She is currently pursuing a PhD in Cryptography at the Faculty of Information Technology, Czech Technical University (CTU) in Prague, Czech Republic. She also works as a teacher assistant at CTU, teaching courses on cryptography, mathematics and cybersecurity, and recently also a new course called "Human Factors in Cryptography and Security", which aims to bring an inter-disciplinary point of view to computer science students.
January 30, 2025, 10:00 am +Zoom (click here)
Speaker: Eliana Carozza (PhD researcher at IRIF, Université Paris Cité, France)
Title: Faster Signatures from MPC-in-the-Head
Abstract: The construction of signature schemes using the MPC-in-the-head paradigm is revisited, leading to two main contributions:
It is observed that prior signatures within the MPC-in-the-head paradigm require a salted version of the GGM puncturable pseudorandom function (PPRF) to mitigate collision attacks. A new efficient PPRF construction is presented, which is provably secure in the multi-instance setting. The security analysis, conducted in the ideal cipher model, represents a core technical contribution. Unlike previous constructions that relied on hash functions, the proposed PPRF uses only a fixed-key block cipher, resulting in significant efficiency gains, with speed improvements ranging from 12× to 55× for a recent signature scheme (Joux and Huth, Crypto’24). This improved PPRF has the potential to enhance the performance of various MPC-in-the-head signatures.
A new signature scheme is introduced, based on the regular syndrome decoding assumption and a novel protocol for the MPC-in-the-head paradigm. The proposed scheme achieves a substantial reduction in communication overhead compared to earlier works. Despite its conceptual simplicity, the security analysis involves intricate combinatorial considerations.
January 16, 2025, 10:00 am +Zoom (click here)
Speaker: Edoardo Persichetti, Ph.D. Florida Atlantic University
Title: On Digital Signatures from Cryptographic Group Actions”
Abstract: Cryptography based on group actions has been studied for a long time. In recent years, however, the area has seen a revival, partially due to its role in post-quantum cryptography. In this talk, we present our work on a unified taxonomy of a variety of techniques used to design digital signature schemes. We describe all techniques in a single fashion, show how they impact the performance of the resulting protocols and analyse how different techniques can be combined for optimal performance.
December 5, 2024, 10:00 am +Zoom (click here)
Speaker: Abhraneel Dutta, Ph.D., Florida Atlantic University
Title: Polynomial Inversion Algorithms in Constant Time for Post-Quantum Cryptography
Abstract: The computation of the inverse of a polynomial over a quotient ring or a finite field plays a very important role during the key generation of post-quantum cryptosystems like NTRU, BIKE, and LEDACrypt. It is therefore important that there exist an efficient algorithm capable of running in constant time, to prevent timing side-channel attacks. In this article, we study both constant-time algorithms based on Fermat's Little Theorem and the Extended GCD Algorithm, and provide a detailed comparison in terms of performance. According to our conclusion, we see that the constant-time Extended GCD-based Bernstein-Yang's algorithm shows a better performance with 1.76x-3.76x on x86 platforms compared to FLT-based methods. Although we report numbers from a software implementation, we additionally provide a short glimpse of some recent results when these two algorithms are implemented on various hardware platforms. Finally, we also explore other exponentiation algorithms that work similarly to the Itoh-Tsuji inversion method. These algorithms perform fewer polynomial multiplications and show a better performance with 1.56x-1.96x on x86 platform compared to Itoh-Tsuji inversion method.
November 14, 2024, 10:00 am
Speaker: Merey Sarsengeldin, Visiting Scholar, Department of Mathematics, University of Central Florida FLYER
Title: Variational Quantum Neural Network for modeling and solving Heat and Mass transfer problems.
Abstract: In this study we present a hybrid quantum-classical neural network (Variational Quantum Algorithm) to model and solve heat and mass transfer problems. The underlying PDEs responsible for modeling diverse phenomena are Stefan Type Problems. These problems are nonlinear where along with the unknown temperature function unknown boundary or flux function has to be determined. This kind of Free Boundary Value Problems are hard to solve analytically. To solve such kind problems analytically and numerically, we benefit from computational power of Quantum Computing and utilize neural networks as a universal function approximator to find the Heat function and Moving Phase boundary. On the basis of the Variational Quantum Neural Network, we have developed methodological framework and software artifact which might be of interest and beneficial for researchers and engineers working in the field of modeling Heat and Mass transfer phenomena.
October 31, 2024, 10:00 am
Speaker: Dr. Francesco Sica, Assistant Professor, Florida Atlantic University FLYER
Title: Group Actions and the Discrete Log Problem
Abstract: The discrete logarithm problem (DLP) asks to compute, in a cyclic group $G=\langle g \rangle$, given $x\in G$ and $y= x^k$, the exponent $k$. This problem can be generalized to a situation when $G$ acts on a set $X$, and gives rise to the analogous vectorization problem (VP), asking to recover $\gamma\in G$ from knowledge of $x\in X$ and $y=\gamma \cdot x$.
We will discuss generic algorithms to solve the VP, in particular in the presence of hints $z=\gamma^d \cdot x$, rephrasing a 2006 argument of Cheon.
October 17, 2024, 10:00 am
Speaker: Ruslan Ospanov (Eurasian National University, Kazakhstan)
Title: The MCDM-RL-based Framework for Consensus Protocol Selection for IoT networks.
Abstract. This topic is a part of my PhD research topic: “Design and analysis of cryptographic algorithms and protocols for solving the problem of consensus in distributed ledger technologies”.
Reinforcement learning (RL) has played a key role in the rapid development of artificial intelligence technologies that has been observed over the past decade. Reinforcement learning methods have shown impressive results in a range of fields. Specifically, RL is widely applied in robotics, control systems, and the Internet of Things (IoT) to address challenges in automation, optimization, and the management of complex systems. The IoT is also a major area for the implementation of distributed ledger and blockchain technologies, which provide effective solutions to overcome the limitations of conventional IoT applications. A key element of the distributed ledger reference architecture is the consensus layer, which handles agreement among network nodes, ensuring the ledger’s state remains consistent while maintaining data security, accuracy, and protection. The selection of a consensus protocol plays a crucial role in determining the performance and security of the blockchain system.
This talk is devoted to the issue of selection a blockchain consensus protocol for IoT networks using the combined application of multi-criteria decision making (MCDM) and reinforcement learning (RL) methods. In this talk, I will consider an idea of integration multi-criteria decision making and reinforcement learning methods to blockchain consensus protocol selection for IoT. It proposes a combined consensus protocol selection and management system for IoT networks based on the multi-criteria decision making method and reinforcement learning.
Bio: Ruslan Ospanov has been engaged in scientific and educational activities in the field of mathematics and cryptography for more than 20 years, has dozens of scientific and scientific-methodological works, as well as several copyright certificates from Qazpatent (National Institute of Intellectual Property of the Ministry of Justice of the Republic of Kazakhstan (NIIP)). He worked as a teacher in various universities of Kazakhstan (Karaganda State University named after academician E.A. Buketov, L.N. Gumilyov Eurasian National University and other). He is also a research fellow at the Research Institute of Information Security and Cryptology of L.N. Gumilyov Eurasian National University. Since September 2022, he has been a doctoral student at the Eurasian National University named after L.N. Gumilyov, specializing in Information Security Systems.
October 3, 2024, 10:00 am
Speaker: Dr. Veronika Kuchta, Assistant Professor, Florida Atlantic University FLYER
Title: Proximity gaps for Reed-Solomon Codes and their Application in Interactive Oracle Proofs of Proximity and ZK-SNARKs
Abstract: Reed-Solomon codes have long been a fundamental tool of error correction and data integrity, but their applications extend far beyond traditional coding theory. In this talk, I will explore the concept of proximity gaps within Reed-Solomon codes—specific measures of how far a received word is from the closest codeword—and their critical role in the design and analysis of advanced cryptographic protocols, such as Zero-Knowledge Succinct Non-Interactive Arguments of Knowledge (ZK-SNARKs) and Interactive Oracle Proofs of Proximity (IOPPs).
September 19, 2024, 10:00 am
Speaker: Dr. Shi Bai, Associate Professor, Florida Atlantic University FLYER
Title: Lattice-based Cryptography: Construction and Analysis
Abstract: Lattice-based Cryptography holds a great promise for post-quantum cryptography. It enjoys strong security based on the so-called worst-case to average-case redution; relatively efficient implementations, as well as algorithmic simplicity. In this talk, we will discuss a post-quantum scheme based on lattice; and several algorithms for evaluating the security of average-case/worst-case problems in lattice-based cryptography.
September 5, 2024, 10:00 am
Speaker: Dr. Edoardo Persichetti, Associate Professor, Florida Atlantic University FLYER
Title: A Brief Introduction to Code-Based Cryptography
Abstract: Code-based cryptographic primitives are among the main solutions for Post-Quantum Cryptography, the area of study in charge of protecting our information and communication in the presence of quantum adversaries. In this talk, I will briefly walk through the history of this field, highlighting the main constructions, modern approaches, and recent developments. Everyone welcome!
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