Measuring the security of cryptographic systems is not a simple task. Nevertheless, there is an increasing need for a cryptographic metric which could assist in decision making when choosing between various candidates. The National Institute of Standards and Technology (NIST) has launched a process to standardize quantum-resistance public key encryption, key encapsulation and digital signature algorithms. This is NIST’s response to the threat posed by quantum computers against classical public key cryptography. In this paper, we apply a metric taxonomy, produced by earlier studies, to two NIST third round finalist digital signature algorithms Dilithium and Falcon in order to asses the effectiveness and extensiveness of the metric. Although, our results show that clear differences can be found with used metrics, we propose some improvements to them to allow more comprehensive analysis.
Measuring the security of cryptographic systems is not a simple task. Nevertheless, there is an increasing need for a cryptographic metric which could assist in decision making when choosing between various candidates. The National Institute of Standards and Technology (NIST) has launched a process to standardize quantum-resistance public key encryption, key encapsulation and digital signature algorithms. This is NIST’s response to the threat posed by quantum computers against classical public key cryptography. In this paper, we apply a metric taxonomy, produced by earlier studies, to two NIST third round finalist digital signature algorithms Dilithium and Falcon in order to asses the effectiveness and extensiveness of the metric. Although, our results show that clear differences can be found with used metrics, we propose some improvements to them to allow more comprehensive analysis.
The National Institute of Standards and Technology (NIST) has recently concluded the third round of its Post Quantum Cryptography Standardization Process, selecting four finalist algorithms for standardization: CRYSTALS Kyber, CRYSTALS-Dilithium, FALCON, and SPHINCS+. These algorithms are designed to withstand attacks from both classical and quantum computers, ensuring the long-term security of digital communications. This paper presents a comprehensive comparative analysis of the security margins and practical deployment readiness of these finalist algorithms. CRYSTALS-Kyber, a key encapsulation mechanism based on the hardness of the Module Learning With Errors problem, offers strong security and efficient performance. CRYSTALS-Dilithium, a digital signature algorithm based on module lattices, provides robust security guarantees and relatively straightforward implementation. FALCON, a lattice-based digital signature algorithm utilizing the Fast Fourier Transform, offers compact signatures and fast verification but faces implementation challenges due to its reliance on floating-point arithmetic. SPHINCS+, a hash-based signature scheme, stands out as a conservative choice with security based solely on the well-established security of hash functions. The analysis reveals that while each algorithm has its strengths, they also face unique challenges in terms of side-channel vulnerabilities, formal security proofs, and performance trade-offs. The practical deployment of these algorithms requires careful consideration of specific security requirements, performance needs, and resource constraints. Ongoing research efforts aim to enhance the algorithms' resistance against advanced attacks, optimize their performance across diverse platforms, and develop standardized and secure hybrid cryptographic systems. The transition to post-quantum cryptography will involve challenges such as interoperability with legacy systems, the need for clear standards and regulatory guidance, and the costs associated with software and hardware updates. Continued engagement with the cryptographic community and monitoring of the evolving security landscape will be crucial for ensuring a secure and effective migration to post-quantum cryptography.
Public Key Infrastructure (PKI) generates and distributes digital certificates to provide the root of trust for securing digital networking systems. To continue securing digital networking in the quantum era, PKI should transition to use quantum-resistant cryptographic algorithms. The cryptography community is developing quantum-resistant primitives/algorithms, studying, and analyzing them for cryptanalysis and improvements. National Institute of Standards and Technology (NIST) selected finalist algorithms for the post-quantum digital signature cipher standardization, which are Dilithium, Falcon, and Rainbow. We study and analyze the feasibility and the processing performance of these algorithms in memory/size and time/speed when used for PKI, including the key generation from the PKI end entities (e.g., a HTTPS/TLS server), the signing, and the certificate generation by the certificate authority within the PKI. The transition to post-quantum from the classical ciphers incur changes in the parameters in the PKI, for example, Rainbow I significantly increases the certificate size by 163 times when compared with RSA 3072. Nevertheless, we learn that the current X.509 supports the NIST post-quantum digital signature ciphers and that the ciphers can be modularly adapted for PKI. According to our empirical implementations-based study, the post-quantum ciphers can increase the certificate verification time cost compared to the current classical cipher and therefore the verification overheads require careful considerations when using the post-quantum-cipher-based certificates.
The advent of quantum computing will pose a substantial threat to the security of classical cryptographic methods, which could become vulnerable to quantum-based attacks. In response to this impending challenge, the field of post-quantum cryptography has emerged, aiming to develop algorithms that can withstand the computational power of quantum computers. This study addressed the pressing concern of classical cryptographic methods becoming vulnerable to quantum-based attacks due to the rise of quantum computing. The emergence of post-quantum cryptography has led to the development of new resistant algorithms. Our research focused on four quantum-resistant algorithms endorsed by America’s National Institute of Standards and Technology (NIST) in 2022: CRYSTALS-Kyber, CRYSTALS-Dilithium, FALCON, and SPHINCS+. This study evaluated the security, performance, and comparative attributes of the four algorithms, considering factors such as key size, encryption/decryption speed, and complexity. Comparative analyses against each other and existing quantum-resistant algorithms provided insights into the strengths and weaknesses of each program. This research explored potential applications and future directions in the realm of quantum-resistant cryptography. Our findings concluded that the NIST algorithms were substantially more effective and efficient compared to classical cryptographic algorithms. Ultimately, this work underscored the need to adapt cryptographic techniques in the face of advancing quantum computing capabilities, offering valuable insights for researchers and practitioners in the field. Implementing NIST-endorsed quantum-resistant algorithms substantially reduced the vulnerability of cryptographic systems to quantum-based attacks compared to classical cryptographic methods.
Quantum computing challenges the mathematical problems anchoring the security of the classical public key algorithms. For quantum-resistant public key algorithms, the National Institute of Standards and Technology (NIST) has undergone a multi-year standardization process and selected the post-quantum cryptography (PQC) public key digital signatures of Dilithium, Falcon, and SPHINCS+. Finding common ground to compare these algorithms can be difficult because of their design differences, including the fundamental math problems (lattice-based vs. hash-based). We use a visualization model to show the key/signature size vs. security trade-offs for all PQC algorithms. Our performance analyses compare the algorithms’ computational loads in the execution time. Building on the individual algorithms’ analyses, we analyze the communication costs and implementation overheads when integrated with Public Key Infrastructure (PKI) and with Transport Layer Security (TLS) and Transmission Control Protocol (TCP)/Internet Protocol (IP). Our results show that the lattice-based algorithms of Dilithium and Falcon induce lower computational overheads than the hash-based algorithms of SPHINCS+. In addition, the lattice-based PQC can outperform the classical algorithm with comparable security strength; for example, Dilithium 2 and Falcon 512 outperform RSA 4096 in the TLS handshake time duration.
Information security is a fundamental and urgent issue in the digital transformation era. Cryptographic techniques and digital signatures have been applied to protect and authenticate relevant information. However, with the advent of quantum computers and quantum algorithms, classical cryptographic techniques have been in danger of collapsing because quantum computers can solve complex problems in polynomial time. Stemming from that risk, researchers worldwide have stepped up research on post-quantum algorithms to resist attack by quantum computers. In this review paper, we survey studies in recent years on post-quantum cryptography (PQC) and provide statistics on the number and content of publications, including a literature overview, detailed explanations of the most common methods so far, current implementation status, implementation comparisons, and discussion on future work. These studies focused on essential public cryptography techniques and digital signature schemes, and the US National Institute of Standards and Technology (NIST) launched a competition to select the best candidate for the expected standard. Recent studies have practically implemented the public key encryption/key encapsulation mechanism (PKE/KEM) and digital signature schemes on different hardware platforms and applied various optimization measures based on other criteria. Along with the increasing number of scientific publications, the recent trend of PQC research is increasingly evident and is the general trend in the cryptography industry. The movement opens up a promising avenue for researchers in public key cryptography and digital signatures, especially on algorithms selected by NIST.
The advent of quantum computing poses a significant threat to current cryptographic systems, particularly public-key algorithms such as RSA and ECC, which are vulnerable to quantum attacks like Shor's algorithm. Post-Quantum Cryptography (PQC) aims to develop and standardize quantum-resistant cryptographic algorithms to secure digital communications in the quantum era. This paper examines the current landscape of PQC, focusing on the evaluation and standardization efforts led by organizations such as the National Institute of Standards and Technology (NIST). We analyze the major families of quantum-resistant algorithms, including lattice-based, hash-based, code-based, multivariate, and isogeny-based cryptography, discussing their security guarantees, performance trade-offs, and implementation challenges. Furthermore, we review NIST's PQC standardization process, highlighting selected finalists and alternate candidates, and explore the ongoing transition challenges in adopting these algorithms across industries. Finally, we discuss future directions for PQC research, including hybrid cryptographic systems and the need for continued cryptanalysis to ensure long-term security. This work provides a comprehensive overview of the progress and challenges in deploying quantum-resistant cryptography to safeguard against emerging quantum threats.