Aim: The imminent advent of large-scale quantum computers within the next years is expected to highly affect the security of several cryptosystems that are now considered secure; this mainly holds for classical, long-established, public key cryptographic algorithms such as RSA and elliptic curve cryptography. Apparently, any security protocol that relies on such ciphers, including the transport layer security (TLS) protocol which constitutes a somewhat de facto standard for the security on the web, will not be considered secure in the post-quantum era. To alleviate the security risks stemming from quantum computing, several proposals have been submitted to the relevant procedure initiated by NIST towards evaluating and standardizing one or more quantum-resistant public-key cryptographic algorithms. This paper focuses on embedding post-quantum secure cryptographic algorithms into the TLS protocol to analyze its performance. More precisely, the paper aims to analyze whether this transition to post-quantum secure algorithms will have a significant impact on the user experience due to the possible increase of client--server communication times. Methods: Having as the starting point several important works in the field, several experiments were carried out, using combinations of cloud and local virtual machines per case and considering all the post-quantum cryptographic algorithm finalists for key exchange from the third round of the ongoing NIST process, for various cryptographic as well as network parameters. Results: Our results exhibit that, for key exchange in TLS, the best performance among the post-quantum secure ciphers is achieved by the Saber and CRYSTAL-Kyber variants for all security levels, regardless of the underlying computing power. The performance is comparable to that of the corresponding one achieved by a classical elliptic curve algorithm for key exchange for both RTT and packet loss ratio — i.e., the network parameters seem to have the same effect on post-quantum secure algorithms as in the case of a conventional elliptic curve algorithm. However, the effect of the network parameters on the performance is more crucial than the effect of the underlying chosen ciphers. Conclusion: According to the experiments, we conclude that there exist very promising algorithms that could be utilized in TLS in the near future, which may behave even better than the conventional elliptic curve algorithms for key exchange. It should also be pointed out that NIST announced on 5 July 2022 (i.e., after the completion of our research experiments) that, for general encryption used when we access secure websites, the CRYSTALS-Kyber algorithm has been selected, having as one of its advantages the speed of operation. Hence, the results of our paper are fully in line with the progress of the NIST process. Taking into account that the NIST process is still ongoing (now in its fourth round) with the aim to select more algorithms, as well as that some algorithms may be standardized outside NIST, it becomes evident that our results provide very useful insights on performance aspects of the post-quantum secure algorithms.
Aim: The imminent advent of large-scale quantum computers within the next years is expected to highly affect the security of several cryptosystems that are now considered secure; this mainly holds for classical, long-established, public key cryptographic algorithms such as RSA and elliptic curve cryptography. Apparently, any security protocol that relies on such ciphers, including the transport layer security (TLS) protocol which constitutes a somewhat de facto standard for the security on the web, will not be considered secure in the post-quantum era. To alleviate the security risks stemming from quantum computing, several proposals have been submitted to the relevant procedure initiated by NIST towards evaluating and standardizing one or more quantum-resistant public-key cryptographic algorithms. This paper focuses on embedding post-quantum secure cryptographic algorithms into the TLS protocol to analyze its performance. More precisely, the paper aims to analyze whether this transition to post-quantum secure algorithms will have a significant impact on the user experience due to the possible increase of client--server communication times. Methods: Having as the starting point several important works in the field, several experiments were carried out, using combinations of cloud and local virtual machines per case and considering all the post-quantum cryptographic algorithm finalists for key exchange from the third round of the ongoing NIST process, for various cryptographic as well as network parameters. Results: Our results exhibit that, for key exchange in TLS, the best performance among the post-quantum secure ciphers is achieved by the Saber and CRYSTAL-Kyber variants for all security levels, regardless of the underlying computing power. The performance is comparable to that of the corresponding one achieved by a classical elliptic curve algorithm for key exchange for both RTT and packet loss ratio — i.e., the network parameters seem to have the same effect on post-quantum secure algorithms as in the case of a conventional elliptic curve algorithm. However, the effect of the network parameters on the performance is more crucial than the effect of the underlying chosen ciphers. Conclusion: According to the experiments, we conclude that there exist very promising algorithms that could be utilized in TLS in the near future, which may behave even better than the conventional elliptic curve algorithms for key exchange. It should also be pointed out that NIST announced on 5 July 2022 (i.e., after the completion of our research experiments) that, for general encryption used when we access secure websites, the CRYSTALS-Kyber algorithm has been selected, having as one of its advantages the speed of operation. Hence, the results of our paper are fully in line with the progress of the NIST process. Taking into account that the NIST process is still ongoing (now in its fourth round) with the aim to select more algorithms, as well as that some algorithms may be standardized outside NIST, it becomes evident that our results provide very useful insights on performance aspects of the post-quantum secure algorithms.
The emergence of quantum computing presents a significant threat to classical cryptographic primitives, particularly those employed in securing internet communications via widely used protocols such as Transport Layer Security (TLS). As conventional key exchange mechanisms will become increasingly vulnerable in the post-quantum era, the integration of post-quantum cryptographic (PQC) algorithms into existing security protocols is of utmost importance. This study investigates the impact of incorporating PQC key encapsulation mechanisms—specifically, the recent standards CRYSTALS-Kyber and HQC, in conjunction with the candidate standard BIKE—into the TLS 1.3 handshake. A comprehensive experimental evaluation was conducted to measure handshake latency under emulated network conditions with varying packet loss probabilities. The findings offer useful insights into the performance trade-offs introduced by PQC integration and further highlight the necessity of a timely transition to post-quantum cryptographic standards.
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.
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.
The threats are existential to the traditional cryptosystems of public keys, including RSA, Diffie-Hellman, and elliptic curve cryptography (ECC), due to the rapid progress in quantum computing. Such algorithms as the Shor and Grover algorithms prove that as soon as large scale quantum computers are achieved, these classical cryptographic protocols will not provide any privacy and integrity to online communication. This has created an emergency to find post-quantum cryptography (PQC), or quantum-safe cryptography, which will resist attacks by both classical and quantum attackers. The paper is a review of the latest research and development in post-quantum cryptographic algorithms and their implementation in current security systems. We organize quantum-safe methods into significant organizations such as lattice-based, hash-based, multivariate polynomial-based and code-based encrypted communications. Each type has been evaluated critically based on computational efficiency, key sizes, speed of encryption/decryption and security proofs. The survey also examines the current standardization activities happening in the world and especially the U.S. National Institute of Standards and Technology (NIST) PQC competition, which lists candidate algorithms that have advanced to standard adoption. Besides this, the paper addresses hybrid cryptographic designs that use both classical and post-quantum bases in ensuring a seamless migration in the transition phase. Internet security protocols like TLS, VPNs and blockchain consensus as applications of PQC are examined in detail. Lastly, we pinpoint open research issues, which include creating lightweight PQC to support resource-constrained IoT devices, balancing performance and strong security assurances, and interoperability between the new PQC algorithms and existing infrastructures. Through detailed survey we inform the future of researchers, practitioners, and policymakers on the preparation of the post-quantum era of secure digital communications.
The emergence of large-scale quantum computing presents an imminent threat to contemporary public-key cryptosystems, with quantum algorithms such as Shor’s algorithm capable of efficiently breaking RSA and elliptic curve cryptography (ECC). This vulnerability has catalyzed accelerated standardization efforts for post-quantum cryptography (PQC) by the U.S. National Institute of Standards and Technology (NIST) and global security stakeholders. While theoretical security analysis of these quantum-resistant algorithms has advanced considerably, comprehensive real-world performance benchmarks spanning diverse computing environments—from high-performance cloud infrastructure to severely resource-constrained IoT devices—remain insufficient for informed deployment planning. This paper presents the most extensive cross-platform empirical evaluation to date of NIST-selected PQC algorithms, including CRYSTALS-Kyber and NTRU for key encapsulation mechanisms (KEMs), alongside BIKE as a code-based alternative, and CRYSTALS-Dilithium and Falcon for digital signatures. Our systematic benchmarking framework measures computational latency, memory utilization, key sizes, and protocol overhead across multiple security levels (NIST Levels 1, 3, and 5) in three distinct hardware environments and various network conditions. Results demonstrate that contemporary server architectures can implement these algorithms with negligible performance impact (<5% additional latency), making immediate adoption feasible for cloud services. In contrast, resource-constrained devices experience more significant overhead, with computational demands varying by up to 12× between algorithms at equivalent security levels, highlighting the importance of algorithm selection for edge deployments. Beyond standalone algorithm performance, we analyze integration challenges within existing security protocols, revealing that naive implementation of PQC in TLS 1.3 can increase handshake size by up to 7× compared to classical approaches. To address this, we propose and evaluate three optimization strategies that reduce bandwidth requirements by 40–60% without compromising security guarantees. Our investigation further encompasses memory-constrained implementation techniques, side-channel resistance measures, and hybrid classical-quantum approaches for transitional deployments. Based on these comprehensive findings, we present a risk-based migration framework and algorithm selection guidelines tailored to specific use cases, including financial transactions, secure firmware updates, vehicle-to-infrastructure communications, and IoT fleet management. This practical roadmap enables organizations to strategically prioritize systems for quantum-resistant upgrades based on data sensitivity, resource constraints, and technical feasibility. Our results conclusively demonstrate that PQC is deployment-ready for most applications, provided that implementations are carefully optimized for the specific performance characteristics and security requirements of target environments. We also identify several remaining research challenges for the community, including further optimization for ultra-constrained devices, standardization of hybrid schemes, and hardware acceleration opportunities.
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.