The development of quantum computers represents an important advancement in computing, using quantum mechanics to address problems that were previously difficult to solve. This technological advancement poses a challenge for cryptographic systems. While some methods are known to be vulnerable, the impact of quantum computing on symmetric cryptography has received less research attention, largely because the common advice is to simply double the key size. This paper explores how quantum computing affects symmetric cryptography, focusing on block cipher-based cryptography. It surveys existing literature on the quantum resilience of symmetric cryptographic primitives based on block ciphers and their security in various scenarios. Not all symmetric cryptographic functionalities are quantum-secure, and their security depends on the specific adversary model being considered. We provide an overview of the research conducted and pinpoint areas where further investigation is needed.
The development of quantum computers represents an important advancement in computing, using quantum mechanics to address problems that were previously difficult to solve. This technological advancement poses a challenge for cryptographic systems. While some methods are known to be vulnerable, the impact of quantum computing on symmetric cryptography has received less research attention, largely because the common advice is to simply double the key size. This paper explores how quantum computing affects symmetric cryptography, focusing on block cipher-based cryptography. It surveys existing literature on the quantum resilience of symmetric cryptographic primitives based on block ciphers and their security in various scenarios. Not all symmetric cryptographic functionalities are quantum-secure, and their security depends on the specific adversary model being considered. We provide an overview of the research conducted and pinpoint areas where further investigation is needed.
Recent advances in cryptography aim to address threats posed by quantum computers. However, these advances have focused disproportionately on asymmetric schemes, while symmetric primitives like block ciphers have received less attention. The common assumption is that doubling block cipher key sizes provides adequate quantum resistance, but this oversimplifies the challenge. This paper provides a systematic examination of block cipher security in the quantum computing era. The paper first establishes a formal framework for understanding block cipher security, covering their mathematical foundations and essential security properties. Building on this foundation, we examine how quantum computing fundamentally challenges these security assumptions, going beyond the simple impact on key lengths. Our review of recent research reveals that quantum attacks can exploit structural vulnerabilities in block ciphers and their modes of operation, requiring more comprehensive defenses than key length adjustments alone. We analyze emerging approaches in quantum-resistant design and identify critical areas requiring further research to ensure block cipher security in a post-quantum world.
The emergence of quantum computing presents profound implications for classical cryptographic systems, including symmetric encryption. This chapter surveys the impact of quantum computing on symmetric cryptography, outlines key challenges such as reduced security margins and implementation vulnerabilities, and explores mitigation strategies including increased key sizes, quantum-resistant designs, hybrid encryption models, and algorithm agility. Future research directions are discussed, emphasizing the need for quantum-native symmetric primitives, efficient post-quantum implementations, and secure key exchange through quantum key distribution. The chapter advocates for a proactive transition toward quantum-resilient cryptographic infrastructures to ensure long-term data security.
Quantum computers pose a significant threat to blockchain technology's security, which heavily relies on public-key cryptography and hash functions. The cryptographic algorithms used in blockchains, based on large odd prime numbers and discrete logarithms, can be easily compromised by quantum computing algorithms like Shor's algorithm and its future qubit variations. This survey paper comprehensively examines the impact of quantum computers on blockchain security and explores potential mitigation strategies. We begin by surveying the existing literature on blockchains and quantum computing, providing insights into the current state of research. We then present an overview of blockchain, highlighting its key components and functionalities. We delve into the preliminaries and key definitions of quantum computing, establishing a foundation for understanding the implications on blockchain security. The application of blockchains in cybersecurity is explored, considering their strengths and vulnerabilities in light of evolving quantum computing capabilities. The survey focuses on the quantum security of blockchain's fundamental building blocks, including digital signatures, hash functions, consensus algorithms, and smart contracts. We analyze the vulnerabilities introduced by quantum computers and discuss potential countermeasures and enhancements to ensure the integrity and confidentiality of blockchain systems. Furthermore, we investigate the quantum attack surface of blockchains, identifying potential avenues for exploiting quantum computing to strengthen existing attacks. We emphasize the need for developing quantum-resistant defenses and explore solutions for mitigating the threat of quantum computers to blockchains, including the adoption of quantum and post-quantum blockchain architectures. By examining vulnerabilities and discussing mitigation strategies, we aim to guide researchers, practitioners, and policymakers in developing robust and secure blockchain systems capable of withstanding advancements in quantum computing technology.
With the rapid advancement regarding quantum computing, traditional cryptographic systems face an existential threat because of their reliance concerning mathematical challenges which may be addressed effectively solved using quantum algorithms like the one developed by Shor. This imminent risk has driven extensive research into quantum-resistant cryptography (PQC), that seeks to develop encryption methods resilient against attacks powered by quantum computing. This study offers a thorough literature survey on high-level security techniques in quantum security for PQC, analysing past and current research efforts in this domain. We first examine the vulnerabilities of classical cryptographic protocols, including public-key encryption methods such as RSA (developed by Rivest, Shamir, and Adleman) and ECC (which uses elliptic curve mathematics), and traditional cryptographic hashing methods, against quantum adversaries. The study then explores the foundational approaches to quantum-secure cryptography, including lattice-based, hash-based, multivariate polynomial, code-based, and isogeny-based encryption methods that possess emerged as promising candidates for standardization. The survey highlights key challenges in the real-world application of PQC, including performance trade-offs, key size overhead, and deployment complexities. We conclude by identifying future research directions during the creation of scalable, efficient, and provably secure cryptographic methods designed to withstand quantum attacks techniques. As the shift toward the quantum-resilient era approaches, this survey aims to provide a clear and structured comprehension of the evolving the domain of quantum security for PQC.
Quantum computers pose a significant threat to blockchain technology’s security, which heavily relies on public-key cryptography and hash functions. The cryptographic algorithms used in blockchains, based on large odd prime numbers and discrete logarithms, can be easily compromised by quantum computing algorithms like Shor’s algorithm and its future qubit variations. This survey paper comprehensively examines the impact of quantum computers on blockchain security and explores potential mitigation strategies. We begin by surveying the existing literature on blockchains and quantum computing, providing insights into the current state of research. We then present an overview of blockchain, highlighting its key components and functionalities. We delve into the preliminaries and key definitions of quantum computing, establishing a foundation for understanding the implications on blockchain security. The application of blockchains in cybersecurity is explored, considering their strengths and vulnerabilities in light of evolving quantum computing capabilities. The survey focuses on the quantum security of blockchain’s fundamental building blocks, including digital signatures, hash functions, consensus algorithms, and smart contracts. We analyze the vulnerabilities introduced by quantum computers and discuss potential countermeasures and enhancements to ensure the integrity and confidentiality of blockchain systems. Furthermore, we investigate the quantum attack surface of blockchains, identifying potential avenues for exploiting quantum computing to strengthen existing attacks. We emphasize the need for developing quantum-resistant defenses and explore solutions for mitigating the threat of quantum computers to blockchains, including the adoption of quantum and post-quantum blockchain architectures. By examining vulnerabilities and discussing mitigation strategies, we aim to guide researchers, practitioners, and policymakers in developing robust and secure blockchain systems capable of withstanding advancements in quantum computing technology.
With the continuous development of quantum technology and the gradual advancement of quantum computers, the challenges faced by modern cryptography are becoming increasingly diverse. When analyzing the security strength of cryptographic algorithms against quantum attacks, the construction of quantum implementation circuits is a crucial aspect. Symmetric-key cryptography is an important component of modern cryptography. This study reviews the research results of optimizing the quantum implementation of symmetric-key cryptography under quantum computing models. Specifically, this work summarizes the construction of reversible circuits for linear layers, Substitution-boxes (S-boxes), and various addition operations, as well as the quantum implementation of symmetric-key ciphers such as AES, SM4, and Camellia.