Quantum-resistant cryptography is cryptography that aims to deliver cryptographic functions and protocols that remain secure even if large-scale fault-tolerant quantum computers are built. NIST will soon announce the first selected public-key cryptography algorithms in its Post-Quantum Cryptography (PQC) standardization which is the most important current effort in the field of quantum-resistant cryptography. This report provides an overview to security experts who do not yet have a deep understanding of quantum-resistant cryptography. It surveys the computational model of quantum computers; the quantum algorithms that affect cryptography the most; the risk of Cryptographically Relevant Quantum Computers (CRQCs) being built; the security of symmetric and public-key cryptography in the presence of CRQCs; the NIST PQC standardization effort; the migration to quantum-resistant public-key cryptography; the relevance of Quantum Key Distribution as a complement to conventional cryptography; and the relevance of Quantum Random Number Generators as a complement to current hardware Random Number Generators.
Quantum-resistant cryptography is cryptography that aims to deliver cryptographic functions and protocols that remain secure even if large-scale fault-tolerant quantum computers are built. NIST will soon announce the first selected public-key cryptography algorithms in its Post-Quantum Cryptography (PQC) standardization which is the most important current effort in the field of quantum-resistant cryptography. This report provides an overview to security experts who do not yet have a deep understanding of quantum-resistant cryptography. It surveys the computational model of quantum computers; the quantum algorithms that affect cryptography the most; the risk of Cryptographically Relevant Quantum Computers (CRQCs) being built; the security of symmetric and public-key cryptography in the presence of CRQCs; the NIST PQC standardization effort; the migration to quantum-resistant public-key cryptography; the relevance of Quantum Key Distribution as a complement to conventional cryptography; and the relevance of Quantum Random Number Generators as a complement to current hardware Random Number Generators.
Quantum computing poses a significant threat to conventional cryptographic systems that rely on the difficulty of mathematical problems such as integer factorization and discrete logarithms. These systems underpin much of the current security infrastructure, including public key cryptography and digital signatures. As quantum computers approach practical viability, there is an urgent need to transition to quantum-resistant cryptographic solutions that can secure digital communications against adversaries equipped with quantum capabilities. This paper explores the landscape of quantum-resistant cryptography, focusing on those algorithms that have emerged either as standards or as leading algorithm. Furthermore, the paper examines the progress of standardization efforts, such as the National Institute of Standards and Technology (NIST) Post-Quantum Cryptography (PQC) initiative, and the implications of deploying these algorithms in existing systems. By addressing the practical considerations for adoption, this study aims to provide a comprehensive overview of the current state and future directions of quantum-resistant cryptography, ensuring robust security in a post-quantum world.
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.
In recent years, there has been steady progress in the creation of quantum computers. If large-scale quantum computers are implemented, they will threaten the security of many widely used public-key cryptosystems. Key-establishment schemes and digital signatures based on factorization, discrete logarithms, and elliptic curve cryptography will be most affected. Symmetric cryptographic primitives such as block ciphers and hash functions will be broken only slightly. As a result, there has been an intensification of research on finding public-key cryptosystems that would be secure against cryptanalysts with both quantum and classical computers. This area is often called post-quantum cryptography (PQC), or sometimes quantum-resistant cryptography. The goal is to design schemes that can be deployed in existing communication networks and protocols without significant changes. The National Institute of Standards and Technology is in the process of selecting one or more public-key cryptographic algorithms through an open competition. New public-key cryptography standards will define one or more additional digital signatures, public-key encryption, and key-establishment algorithms. It is assumed that these algorithms will be able to protect confidential information well in the near future, including after the advent of quantum computers. After three rounds of evaluation and analysis, NIST has selected the first algorithms that will be standardized as a result of the PQC standardization process. The purpose of this article is to review and analyze the state of NIST's post-quantum cryptography standardization evaluation and selection process. The article summarizes each of the 15 candidate algorithms from the third round and identifies the algorithms selected for standardization, as well as those that will continue to be evaluated in the fourth round of analysis. Although the third round is coming to an end and NIST will begin developing the first PQC standards, standardization efforts in this area will continue for some time. This should not be interpreted as meaning that users should wait to adopt post-quantum algorithms. NIST looks forward to the rapid implementation of these first standardized algorithms and will issue future guidance on the transition. The transition will undoubtedly have many complexities, and there will be challenges for some use cases such as IoT devices or certificate transparency.
Virtually all asymmetric cryptographic schemes currently in use are threatened by the potential development of powerful quantum computers. Although there is currently no definite answer and it is very unclear when or even if CRQC will ever be built and the gap between modern quantum computers and the envisioned CRQC is huge, the risk of creating CRQC means that currently deployed public key cryptography must be replaced by quantum-resistant ones alternatives. For example, information encrypted using modern public key cryptography can be recorded by cryptanalysts and then attacked if a QRQC can be created. The potential harm that CRQC could cause is the basis of the motivation to seek countermeasures, even though we have uncertainties about when and if these computers can be built. Deployed systems that use public key cryptography can also take years to update. Post-quantum cryptography is one way to combat quantum computer threats. Its security is based on the complexity of mathematical problems that are currently considered unsolvable efficiently – even with the help of quantum computers. Post-quantum cryptography deals with the development and research of asymmetric cryptosystems, which, according to current knowledge, cannot be broken even by powerful quantum computers. These methods are based on mathematical problems for the solution of which neither efficient classical algorithms nor efficient quantum algorithms are known today. Various approaches to the implementation of post-quantum cryptography are used in modern research, including: code-based cryptography, lattice-based cryptography, hashing-based cryptography, isogeny-based cryptography, and multidimensional cryptography. The purpose of this work is to review the computational model of quantum computers; quantum algorithms, which have the greatest impact on modern cryptography; the risk of creating cryptographically relevant quantum computers (CRQC); security of symmetric cryptography and public key cryptography in the presence of CRQC; NIST PQC standardization efforts; transition to quantum-resistant public-key cryptography; relevance, views and current state of development of quantum-resistant cryptography in the European Union. It also highlights the progress of the most important effort in the field: NIST's standardization of post-quantum cryptography.
The security of widely used public-key cryptographic algorithms (e.g., RSA, elliptic-curve cryptography) is expected to deteriorate once large-scale and fault-tolerant quantum computers are developed. The potential threat is severe because such algorithms underlie the IT infrastructure in modern society, such as in the financial industry. Although the threat is unlikely to materialize in the foreseeable future, the National Institute of Standards and Technology (NIST) has been in the process of standardizing post-quantum cryptography (PQC), which is designed to be secure against quantum computers. NIST has been scrutinizing the security and performance of 15 candidate algorithms (seven finalists and eight alternates). Standardization should accelerate the migration to PQC around the world, not only within the U.S. government. In this paper, we discuss recent trends in the R&D of quantum computers and the security risks of public-key cryptographic algorithms. Then we review NIST's ongoing progress in standardizing PQC and the responses of other organizations in support of the migration. Finally, we discuss future challenges for the real-world implementation of PQC.
Cryptography is a term that safeguards the security of electronic banking transactions, and emails, and most importantly our country relies on cryptography for national security purposes. Post Quantum Cryptography (PQC) has a major aim of developing newer cryptographic schemes that make the cryptosystem secure against quantum computers. This is a state-of-the-art research topic, and it is encouraged by some security agencies like the National Security Agency (NSA). This paper presents a concise and up-to-date review of post-quantum cryptographic (PQC) algorithms submitted to the National Institute of Standards and Technology (NIST) for standardization. Highlighting the need for cryptographic resilience in the era of quantum computing, the study focuses on the technical evaluation of candidate algorithms, including their performance in terms of time and space efficiency. It also examines the progression of these algorithms through NIST’s multi-round selection process, highlighting key developments and implementation challenges. The paper aims to provide researchers with a clear overview of the current state of PQC standardization and the practical considerations involved in deploying secure, quantum-resistant cryptographic solutions.