In the era of active information technologies and device development, the emergence of portable and general-purpose quantum computers is only a matter of time. And although the benefit of their many times greater efficiency, compared to ordinary bit computers, will be obvious, at the same time, they will bring many vulnerabilities to modern algorithms of cryptography and cybersecurity. To prevent this from happening, society has already started researching post-quantum protocols to replace modern ones. Digital signature protocols were no exception. Thus, one of the approaches was constructing post-quantum digital signature protocols based on hash functions. The first representatives were schemes of one-time signatures based on hash functions, which were protected from the capabilities of quantum computers but had the obvious disadvantage of one-time use. The most famous is the so-called Lamport one-time signature. However, this disadvantage of one-time use has been solved by proposing different schemes of multi-time digital signatures based on the creation and use of many one-time signatures. Thus, chain-based and tree-based schemes of multi-time signatures were proposed. This work is devoted to the implementation and comparison of various multi-time signature schemes. During the research, theoretical estimates of memory usage and time required for the operations of various schemes were given. Further implementation of these schemes and final measurements showed the correspondence of theoretical estimates with empirical results and clearly demonstrated the advantages and disadvantages of different schemes. Thus, tree-based schemes showed the best performance, especially those where the tree is built sequentially. However, in certain cases, it makes sense to use a tree with full-depth construction. Due to the relative novelty and small amount of research in this field, multi-time digital signatures have much room for further research, for example, considering N-ary trees and comparing them with binary ones.
In the era of active information technologies and device development, the emergence of portable and general-purpose quantum computers is only a matter of time. And although the benefit of their many times greater efficiency, compared to ordinary bit computers, will be obvious, at the same time, they will bring many vulnerabilities to modern algorithms of cryptography and cybersecurity. To prevent this from happening, society has already started researching post-quantum protocols to replace modern ones. Digital signature protocols were no exception. Thus, one of the approaches was constructing post-quantum digital signature protocols based on hash functions. The first representatives were schemes of one-time signatures based on hash functions, which were protected from the capabilities of quantum computers but had the obvious disadvantage of one-time use. The most famous is the so-called Lamport one-time signature. However, this disadvantage of one-time use has been solved by proposing different schemes of multi-time digital signatures based on the creation and use of many one-time signatures. Thus, chain-based and tree-based schemes of multi-time signatures were proposed. This work is devoted to the implementation and comparison of various multi-time signature schemes. During the research, theoretical estimates of memory usage and time required for the operations of various schemes were given. Further implementation of these schemes and final measurements showed the correspondence of theoretical estimates with empirical results and clearly demonstrated the advantages and disadvantages of different schemes. Thus, tree-based schemes showed the best performance, especially those where the tree is built sequentially. However, in certain cases, it makes sense to use a tree with full-depth construction. Due to the relative novelty and small amount of research in this field, multi-time digital signatures have much room for further research, for example, considering N-ary trees and comparing them with binary ones.
Public key cryptography plays a pivotal role in maintaining digital security and privacy, with its foundations built on the hardness of certain mathematical problems. However, the emergence of quantum computing threatens the security of current cryptographic systems, making the adoption of post-quantum cryptography (PQC) an urgent necessity. Digital signature schemes are essential components in secure communications, providing authentication, non-repudiation, and data integrity. This paper examines the state of post-quantum digital signature schemes across various cryptographic approaches, including lattice-based, code-based, multivariate polynomial-based, hash-based, symmetric-key-based, and isogeny-based systems, alongside advancements in Multi-Party Computation in the Head (MPC-in-the-head) schemes. The paper then explores application-specific signatures such as blind, undeniable, threshold, chameleon, aggregate, and ring signatures, explaining their main use cases and the existing post-quantum cryptographic classifications that support these constructions individually. Software implementations of selected prominent PQC digital signature schemes were carried out, and their performance was systematically analysed using metrics such as bandwidth consumption, latency, and computational efficiency. These results provide key observations regarding the suitability of different schemes for both resource-constrained and high-performance environments. Subsequently, a detailed literature review of implementations on embedded and hardware platforms is presented, focusing on ARM-based devices and FPGA accelerators to evaluate deployment feasibility beyond general-purpose processors. Based on the software and implementation-level findings, a comparative analysis across software, embedded, and hardware platforms is conducted to highlight architectural influences on performance, scalability, and practicality. Furthermore the cryptanalytic attacks on post-quantum digital signature schemes across various PQC classifications are examined in this paper, taking into account both classical and quantum adversarial models. To evaluate realistic security constraints, implementation-oriented vulnerabilities such as side-channel and fault-based attacks are also examined. In addition, the applicability of post-quantum digital signature schemes within TLS, IoT, and related practical deployment scenarios is analysed. The study also discusses possible directions for further investigation, focusing on the requirement for effective and expandable PQC systems that can satisfy changing cybersecurity requirements. In order to protect sensitive data in the digital era, this study emphasizes the need for implementing quantum-secure systems by fusing theoretical understandings with real-world applications.
The emergence of quantum computers, coupled with relentless advancements in technology, calls for the immediate transition from classical to modern cryptography for efficient data transfer across optic fibers. This paper assesses different proposed post-quantum signature schemes pertaining to their plausibility of being useful against quantum computers’ capabilities. The ability of quantum computers to solve mathematical equations at speeds significantly faster than those of classical computers is remarkable. Existing cryptographic frameworks that depend on discrete logarithms and integer factorization are seriously threatened by this exceptional efficiency. In order to protect sensitive data in a post-quantum world, it may be necessary to reevaluate existing encryption techniques as the introduction of quantum computing has the potential to seriously compromise the security of many popular cryptographic systems. Hence, during the post-quantum epoch, the implementation of cryptographic measures to safeguard the confidentiality, integrity, and authenticity of all data amid the challenges instigated by quantum computers is an undertaking that must be addressed tactically and strategically. This document endeavors to depict the state-of-the-art methodologies in post-quantum cryptography outlining lattice, hash, code, and multivariate polynomial lattice-based schemes. By discussing their advantages, disadvantages, and implementation hurdles, this work seeks to educate academics and industry experts about the steps that must be taken to safeguard digital communications in the age of quantum technology.
The rapid advancement of quantum computing poses a serious threat to classical digital signature algorithms such as RSA and ECDSA, which rely on mathematical problems vulnerable to quantum attacks. Hash-based digital signatures offer a strong post-quantum alternative due to their reliance on cryptographic hash functions and their resistance to both classical and quantum adversaries. This study evaluates the feasibility of hash-based signatures in lightweight and resource-constrained environments by implementing three representative schemes: Lamport One-Time Signatures (OTS), Winternitz One-Time Signatures (WOTS), and Merkle-WOTS. The analysis focuses on key performance factors relevant to constrained devices, including key size, signature size, signing time, and verification speed. Experimental results show that while Lamport OTS provides conceptual simplicity and WOTS offers improved efficiency, the Merkle-WOTS scheme delivers the most practical balance. It supports multiple signatures under a compact public key while maintaining moderate signature sizes and competitive performance. These findings indicate that Merkle-WOTS is a strong candidate for post-quantum authentication in IoT and other lightweight embedded systems.
With the advancement of quantum computing, conventional digital signature algorithms such as RSA and El-Gamal are increasingly vulnerable to quantum attacks. This presents a significant challenge for ensuring the security and integrity of electronic signatures. As a result, there is a need to develop post-quantum signature algorithms that can withstand attacks from quantum computers while maintaining computational efficiency. This study proposes a novel modification of the Merkle post-quantum signature scheme, integrating an optimized version of Lamport’s one-time signature algorithm. The core contribution of this work is the design and implementation of a new algorithm that significantly reduces signature verification time without compromising cryptographic strength. A software implementation of the modified scheme was developed using Python and the PyQt 6 library, allowing for practical testing and analysis. The performance of the modified algorithm was compared against the standard Lamport algorithm using execution time measurements and statistical analysis. The experimental results demonstrate that the modified algorithm significantly improves signature verification speed, reducing the time required by up to 44.81% compared to the standard algorithm. The study presents a more efficient post-quantum Merkle signature scheme with a modified Lamport algorithm that enhances signature verification speed while maintaining strong cryptographic security. The results suggest that the proposed scheme is particularly well-suited for environments where fast authentication of multiple digital signatures is required. Experimental results confirm the advantage of the proposed approach, offering a more efficient solution for secure, high-speed digital authentication in post-quantum environments
Abstract Post-quantum (or quantum-resistant) cryptography refers to a set of cryptographic algorithms that are thought to remain secure even in the world of quantum computers. These algorithms are usually considered to be inefficient because of their big keys, or their running time. However, if quantum computers became a reality, security professionals will not have any other choice, but to use these algorithms. Lamport signature is a hash based one-time digital signature algorithm that is thought to be quantum-resistant. In this paper we will describe some simulation results related to the efficiency of the Lamport signature.
The rapid development of quantum computing poses challenges to the foundations of traditional cryptography. The threats are significant in terms of both asymmetric cryptography (which exposes schemes like RSA and ECC to efficient attacks) and symmetric cryptography, where key sizes must be increased to mitigate these threats. In this paper, we review the evolution of hash-based digital signatures, from early one-time signatures to modern stateless schemes, with an emphasis on their security properties, efficiency, and practical constraints. Moreover, we propose a simple comparative metric that reflects structural symmetry across key parameters such as key size, signature size, and computational cost, enabling a visual clustering of the schemes. We give particular attention to recent developments such as Verkle trees, which preserve symmetric design principles while improving scalability and proof compactness. The study highlights ongoing tradeoffs between stateful and stateless designs and argues for the continued relevance of symmetric cryptographic constructions in building secure, efficient post-quantum systems.