An analysis of current research on cryptography on lattices is given. The analysis takes place in accordance with the most relevant algorithms that have gone through the second stage of the US NIST competition. Some of them are combined — include several similar algorithms from the past stage. For a detailed consideration of them, a number of relevant topics for post-quantum algorithms are presented, which allows them to be described and categorized more substantially
An analysis of current research on cryptography on lattices is given. The analysis takes place in accordance with the most relevant algorithms that have gone through the second stage of the US NIST competition. Some of them are combined — include several similar algorithms from the past stage. For a detailed consideration of them, a number of relevant topics for post-quantum algorithms are presented, which allows them to be described and categorized more substantially
Classical cryptography has been around for a long time in the documented human history, but most classical ciphers were broken and even solved by hand. Shannon introduced the notion of perfect secrecy that formally defines confidentiality in the information-theoretic sense, which is only possible in the restricted scenarios where the message is no longer than the encryption key. The invention of public-key cryptography (the Diffie-Hellman key exchange protocol in 1976 and the RSA crypto-system in 1977) marks the birth of modern cryptography, allowing parties to exchange messages securely without sharing any secrets in advance. Furthermore, it provides computational security based on the conjectured hardness of mathematical problems such as factorization and the discrete logarithm. Public-key cryptography has found numerous applications in the Internet, financial and banking industry, and blockchains, and it plays a crucial role in protecting information security and asset safety. Unfortunately, in the 1990s, Shor proposed efficient quantum algorithms that solve number-theoretic problems, including factorization and discrete logarithms in polynomial time. Once a quantum computer of a particular scale becomes a reality, it will cause a devastating blow to the existing public-key infrastructure. To deal with such a ‘quantum crisis’, academia and industry are looking into the design, analysis and standardization of cryptographic algorithms that can resist quantum computers referred to as post-quantum cryptography (PQC). The National Institute of Standards and Technology (NIST) has been soliciting proposals for the post-quantum public-key algorithms since 2016. More recently, the Chinese Association for Cryptologic Research (CACR) held a competition on designing cryptographic algorithms whose public-key cryptography track focused on post-quantum cryptographic algorithms. Lattice-based cryptography is considered by most to be the mainstream technical route of post-quantum cryptography, which is reflected in the number of proposals (and their percentage of the total) received in the NIST PQC process. To reflect the status quo of post-quantum cryptography, we invite leading experts in this area to contribute three technical perspectives that aim to help readers understand the algorithms, the underlying basic techniques and different technical routes to achieve quantum resistance. The first perspective, presented by Lu and Zhang, introduces public-key cryptographic algorithms whose quantum security is reducible from the conjectured quantum hardness of lattice problems. In particular, they mainly focus on public-key encryption (PKE) and the key encapsulation mechanism (KEM), which are essential building blocks for securing the confidentiality of communication without pre-shared secrets. Both types of crypto-systems are solicited by the NIST PQC standardization and the CACR algorithm design competition. This perspective gives a comprehensive survey on practical lattice-based PKEs/KEMs, and their best-known quantum and classical attacks. Another important post-quantum crypto-system is digital signature, which ensures that three goals of information security are met other than confidentiality, namely, integrity, authentication and non-repudiation. The second perspective is on lattice-based signature by Lyubashevsky. In this perspective, he surveys different techniques in building lattice-based post-quantum crypto-systems, discusses the challenges in overcoming performance issues and gives us state-of-the-art digital signature schemes. In addition to ensuring the ‘static’ security of information in storage and transmission, advanced cryptographic algorithms and protocols can guarantee information security during the computation process (possibly among multiple parties), referred to as privacy-preserving computation. Cryptographic techniques involved in privacy-preserving computation include secure multi-party computation, zero-knowledge proof and fully homomorphic encryption. There is a pressing need to migrate them to the post-quantum era. The third perspective, by Yu and Xie, presents practical instantiations of these algorithms and discusses possible ways to migrate them to their quantum-resistant counterparts. To summarize, post-quantum cryptography has received widespread attention and made significant progress in recent years. Some post-quantum cryptographic algorithms, such as the lattice-based candidate, also have other advantages (e.g., computational efficiency and full homomorphism) over their classical counterparts. Lattice-based cryptography is an emerging field with high theoretical value and wide application, and we encourage young researchers to enter and explore this new and exciting field.
This article describes the main trends in the development of cryptography, in particular, the need for active research in the field of postquantum cryptography. The purpose of the article was to review the latest trends in the field of post-quantum cryptography, due to the emergence of quantum algorithms, in order to reflect the current problems arising in the field of modern cryptography. The main method of research is the analysis of scientific literature for the period from 2016 to 2022. The use of quantum computer and quantum algorithms will significantly reduce the time of cracking keys with encryption and solve some types of cryptographic hash functions, which will lead to a significant increase in the length of keys and a decrease in performance. Due to the great economic influence of the USA, it is necessary to pay attention to the post–quantum NIST contests: from the algorithms under consideration, lattice-based algorithms will be standardized, which are the most reliable and efficient in terms of performance according to NIST, however, in order not to rely only on this type of algorithms, NIST selected alternative algorithms–isogeny–based, code–based, hash–based. So, there is a need to conduct research on the search for post-quantum algorithms of various types, which is confirmed by various NIST competitions. Post-quantum algorithms based on the computational difficulty of solving systems of many quadratic equations with many variables are also effective, such algorithms have not been considered by NIST, but they are relevant for further research. Since updating protocols, schemes and infrastructure objects must be carried out together with the introduction of new cryptographic algorithms, the replacement of currently used cryptographic algorithms can be very destructive and take decades, re-encryption with such a new algorithm of stored information and keys can also be used.
Lattice-Based Cryptosystems and Quantum CryptanalysisQuantum computers are probably coming, though we don't know when-and when they arrive, they will, most likely, be able to break our standard public-key cryptography algorithms.In anticipation of this possibility, cryptographers have been working on quantum-resistant public-key algorithms.The National Institute for Standards and Technology (NIST) has been hosting a competition a since 2017, and there already are several proposed standards.b Most of these are based on lattice problems.The mathematics of lattice cryptography revolve around combining sets of vectors-that's the lattice-in a multi-dimensional space.These lattices are filled with multi-dimensional periodicities.The hard problem c that's used in cryptography is to find the shortest periodicity in a large, random-looking lattice.This can be turned into d a public-key cryptosystem in a variety of different ways.Research has been ongoing since 1996, and there has been some really great work since then-including many practical public-key algorithms.On April 10, Yilei Chen from Tsinghua University in Beijing posted a paper describing a new quantum attack on that shortest-path lattice problem.It's a very dense mathematical paper-63 pages long-and my guess is that only a few cryptographers are able to understand all of its details.(I was not one of them.)But the conclusion was pretty devastating, breaking essentially all of the lattice-based fully homomorphic encryption schemes and coming significantly closer to attacks against the recently proposed (and NIST-approved) lattice key-exchange and signature schemes.However, there was a small but critical mistake in the paper, on the bottom of page 37.It was independently discovered by Hongxun Wu from Berkeley and Thomas Vidick from the Weizmann Institute in Israel eight days later.The attack algorithm in its current form doesn't work.This was discussed last week at the Cryptographers' Panel e at the RSA Conference.Adi Shamir, the "S" in RSA and a 2002 recipient of ACM's A.M. Turing award, described the result as psychologically significant because it shows that there is still a lot to be discovered about quantum
The security of classical public-key cryptosystems, which operate based on the computational intractability of integer factorization and discrete logarithm problems, is profoundly threatened by the rapid development of quantum computing. Post-Quantum Cryptography (PQC) has been proposed to improve security against quantum attacks. Lattice-based cryptography is widely regarded as one of the most promising PQC method because of its proven security, efficient implementation, and functional versatility, and it has achieved significant progress in both algorithmic design and engineering implementation in recent years. This paper presents a systematic survey of the status of research on lattice-based cryptographic algorithms. First, the fundamental theory of lattices and their core hard problems are discussed. Next, the technical characteristics and performance of encryption and key encapsulation mechanisms, digital signature schemes, and key exchange protocols constructed based on lattice hard problems are reviewed and compared. Subsequently, the principles and optimization paths of two key technologies for lattice cryptography implementation, namely polynomial multiplication using the fast Number Theoretic Transform (NTT) and pre-image sampling algorithms, are discussed. Finally, considering the PQC standardization process of the National Institute of Standards and Technology (NIST), an outlook on future research directions for lattice-based cryptography is presented. The research directions include the development of more "succinct" fundamental hard problems, strengthening security proofs, improving algorithm efficiency, and countering novel attacks. This review serves as a reference for promoting the practical deployment and further research of lattice-based cryptography.
Lattice-based cryptography is encryption that uses lattice issues as the basis of a conjecture of the complexity of the worst-case problem. This complexity is considered hard in the world of classical and quantum providing for a primitives design of lattice-based cryptography algorithms. The NIST held a contest to find the best algorithm to implement. This paper compares three finalists of that contest by analyzing the theoretical basis of the lattice problems they hold, with the security of the worst case of the attack through some algorithms, lattices with underlying problems, construction of cryptographic algorithms, and comparative analysis of three finalists of the lattice schemes of the NIST competition. Comparison includes the safety and robustness of the lattice problem used the cryptographic algorithm that is built and finally there will be an analysis in a computational time context to discuss the efficiency algorithm created. Two advantages and disadvantages of each the algorithm finalist are implemented and also described.