Submit to Cryptography Review for Cryptography

Journal Menu

Journal Browser

► Journal Browser

Cryptography, Volume 8, Issue 3 (September 2024) – 6 articles

Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
You may sign up for e-mail alerts to receive table of contents of newly released issues.
PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Reader to open them.

Order results

Result details

Section

Show export options Show export options

Select all

Export citation of selected articles as:

15 pages, 1401 KiB

Open AccessArticle

Entropy Analysis of FPGA Interconnect and Switch Matrices for Physical Unclonable Functions

by Jenilee Jao, Ian Wilcox, Jim Plusquellic, Biliana Paskaleva and Pavel Bochev

Cryptography 2024, 8(3), 32; https://doi.org/10.3390/cryptography8030032 - 15 Jul 2024

Viewed by 228

Abstract

Random variations in microelectronic circuit structures represent the source of entropy for physical unclonable functions (PUFs). In this paper, we investigate delay variations that occur through the routing network and switch matrices of a field-programmable gate array (FPGA). The delay variations are isolated from other components of the programmable logic, e.g., look-up tables (LUTs), flip-flops (FFs), etc., using a feature of Xilinx FPGAs called dynamic partial reconfiguration (DPR). A set of partial designs is created to fix the placement of a time-to-digital converter (TDC) and supporting infrastructure to enable the path delays through the target interconnect and switch matrices to be extracted by subtracting out common-mode delay components. Delay variations are analyzed in the different levels of routing resources available within FPGAs, i.e., local routing and across-chip routing. Data are collected from a set of Xilinx Zynq 7010 devices, and a statistical analysis of within-die variations in delay through a set of the randomly-generated and hand-crafted interconnects is presented. Full article

(This article belongs to the Special Issue Emerging Topics in Hardware Security)

► Show Figures

Figure 1

15 pages, 647 KiB

Open AccessArticle

Lattice-Based Post-Quantum Public Key Encryption Scheme Using ElGamal’s Principles

by Dana Sairangazhykyzy Amirkhanova, Maksim Iavich and Orken Mamyrbayev

Cryptography 2024, 8(3), 31; https://doi.org/10.3390/cryptography8030031 - 8 Jul 2024

Viewed by 905

Abstract

Modern technologies like quantum and cloud computing have reshaped computing, offering immense power and scalability. While beneficial, they also challenge the security of traditional cryptographic systems. Quantum computing threatens RSA and ECC with algorithms like Shor’s algorithm, which can accelerate computations exponentially. This risks exposing these systems to attacks, necessitating quantum-resistant cryptography. Cloud computing poses data security concerns, requiring robust cryptographic mechanisms and access controls. Lattice-based cryptography, leveraging problems like the Short Integer Solution (SIS), emerges as a solution. This paper presents a novel quantum-resistant public key encryption scheme based on ElGamal and SIS, ensuring security against quantum and classical threats in modern cryptographic environments. Full article

► Show Figures

Figure 1

16 pages, 502 KiB

Open AccessArticle

Improve Parallel Resistance of Hashcash Tree

by Mario Alviano and Giada Gabriele

Cryptography 2024, 8(3), 30; https://doi.org/10.3390/cryptography8030030 - 8 Jul 2024

Viewed by 269

Abstract

Denial of Service (DoS) attacks remain a persistent threat to online systems, necessitating continual innovation in defense mechanisms. In this work, we present an improved algorithm for mitigating DoS attacks through the augmentation of client puzzle protocols. Building upon the foundation of hashcash trees, a recently proposed data structure combining hashcash and Merkle trees, we introduce a new version of the data structure that enhances resistance against parallel computation (a common tactic employed by attackers). By incorporating the labels of children and the next node in a breadth-first traversal into the hash function, we establish a sequential processing order that inhibits parallel node evaluation. The added dependency on the next node significantly elevates the complexity of constructing hashcash trees, introducing a linear number of synchronization points and fortifying resilience against potential attacks. Empirical evaluation demonstrates the efficacy of our approach, showcasing its ability to accurately control puzzle difficulty while bolstering system security against DoS threats. Full article

► Show Figures

Figure 1

23 pages, 519 KiB

Open AccessArticle

Public Key Protocols from Twisted-Skew Group Rings

by Javier de la Cruz, Edgar Martínez-Moro, Steven Muñoz-Ruiz and Ricardo Villanueva-Polanco

Cryptography 2024, 8(3), 29; https://doi.org/10.3390/cryptography8030029 - 5 Jul 2024

Viewed by 488

Abstract

This article studies some algebraic structures known as twisted-skew group rings in the context of public key cryptography. We first present some background related to these structures to then specifically introduce particular twisted-skew group rings and show how to utilize them as the underlying algebraic structure to build cryptographic protocols. We closely follow an incremental-like methodology to construct these protocols by putting parts together. As as result, we first introduce a key-agreement protocol and then generalize it to a group key-agreement protocol. We then proceed to construct a probabilistic public key encryption from our two-party key agreement and, finally, introduce a key-encapsulation mechanism from a well-known generic construction applied to probabilistic public encryption. Furthermore, we provide an in-depth security analysis for each cryptographic construction under new related algebraic assumptions and supply a proof-of-concept implementation for various candidate chosen groups. Full article

13 pages, 1408 KiB

Open AccessArticle

Efficient and Universal Merkle Tree Inclusion Proofs via OR Aggregation

by Oleksandr Kuznetsov, Alex Rusnak, Anton Yezhov, Dzianis Kanonik, Kateryna Kuznetsova and Oleksandr Domin

Cryptography 2024, 8(3), 28; https://doi.org/10.3390/cryptography8030028 - 5 Jul 2024

Viewed by 478

Abstract

Zero-knowledge proofs have emerged as a powerful tool for enhancing privacy and security in blockchain applications. However, the efficiency and scalability of proof systems remain a significant challenge, particularly in the context of Merkle tree inclusion proofs. Traditional proof aggregation techniques based on AND logic suffer from a high verification complexity and data communication overhead, limiting their practicality for large-scale applications. In this paper, we propose a novel proof aggregation approach based on OR logic, which enables the generation of compact and universally verifiable proofs for Merkle tree inclusion. By adapting and extending the concept of OR composition from Sigma protocols, we achieve a proof size that is independent of the number of leaves in the tree, and verification can be performed using any single valid leaf hash. This represents a significant improvement over AND aggregation, which requires the verifier to process all leaf hashes. We formally define the OR aggregation logic; describe the process of generating universal proofs; and provide a comparative analysis that demonstrates the advantages of our approach in terms of proof size, verification data, and universality. Furthermore, we discuss the potential of combining OR and AND aggregation logics to create complex acceptance functions, enabling the development of expressive and efficient proof systems for various blockchain applications. The proposed techniques have the potential to significantly enhance the scalability, efficiency, and flexibility of zero-knowledge proof systems, paving the way for more practical and adaptive solutions in large-scale blockchain ecosystems. Full article

(This article belongs to the Special Issue Advances in Authentication, Authorization and Privacy for Securing Smart Communications)

► Show Figures

Figure 1

31 pages, 382 KiB

Open AccessArticle

The Emerging Challenges of Wearable Biometric Cryptosystems

by Khalid Al Ajlan, Tariq Alsboui, Omar Alshaikh, Isa Inuwa-Dute, Saad Khan and Simon Parkinson

Cryptography 2024, 8(3), 27; https://doi.org/10.3390/cryptography8030027 - 21 Jun 2024

Viewed by 618

Abstract

Cryptographic key generation and data encryption and decryption using wearable biometric technologies is an emerging research area with significant potential for authentication and communication security. The research area is rapidly developing, and a comprehensive review of recently published literature is necessary to establish emerging challenges. This research article aims to critically investigate and synthesize current research using biometric cryptosystems that use behavior or medico-chemical characteristics, ranging from gate analysis to gaze tracking. The study will summarize the state of knowledge, identify critical research gaps, and provide insight into promising future implications and applications that can enable the realization of user-specific and resilient solutions for authentication and secure communication demands. Full article

(This article belongs to the Special Issue Security, Privacy and Trust Aspects of Wearable and Resource Constrained Devices)

► Show Figures