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.
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.
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.
Development of Quantum Computers are growing rapidly, the security of today’s cryptographic systems which are working with Public Key Infrastructure (PKI) is at serious risk. RSA and ECC algorithms are the backbone of secure communication and digital identity can be breakable by quantum algorithms such as Shor’s. Hence, a transition is required to Post-Quantum Cryptography (PQC), which is designed to handle quantum attacks. This work provides a detailed review of how PQC can be integrated with the existing PKI, with a special focus on the auto-enrollment process. Auto-enrollment is an essential process but often overlooked mechanism, responsible for automatically issuing and renewing digital certificates. First, we explored how current PKI systems are exposed to the quantum threats and the readiness. The performance of the algorithms that are standardized by NIST, such as Kyber and Dilithium were discussed. We analyze the technical and operational challenges of transitioning to PQC by referencing both research studies and real-world implementations from major industry players such as Google and Microsoft. These include large key size, certificate size, compatibility issues, complex computations and need for crypto-agility. We also examine the hybrid approaches that combine classical and post-quantum methods as traditional strategies. The survey concludes by outlining best practices, deployment considerations, and open research challenges that must be addressed for a smooth, secure, and scalable shift to quantum-safe PKI. This work aims to guide researchers, engineers, and policymakers in building the next generation of cryptographic infrastructure that can stand the test-time even in a quantum world.
As the quantum computing era approaches, securing classical cryptographic protocols becomes imperative. Public key cryptography is widely used for signature and key exchange but it’s the type of cryptography more threatened by quantum computing. Its application typically requires support via a public-key certificate, which is a signed data structure and must therefore face twice the quantum challenge: for the certified keys and for the signature itself. We present the latest developments in selecting robust Post-Quantum algorithms and investigate their applicability in the Public Key Infrastructure context. Our contribution entails defining requirements for a secure transition to a quantum-resistant Public Key Infrastructure, with a focus on adaptations for the X.509 certificate format. Additionally, we explore transitioning Certificate Revocation List and Online Certificate Status Protocol to support quantum-resistant algorithms. Through comparative analysis, we elucidate the complex transition to a quantum-resistant PKI.
Quantum computing is developing quickly, and that's a big problem for traditional encryption techniques such as RSA and elliptic curve cryptography. Shor's algorithm, a quantum algorithm, specifically calls into question the long-term security that Public Key Infrastructures (PKIs) currently rely on. So, this thesis investigates how new post-quantum cryptography methods can be integrated into the public key infrastructure that businesses already use. This thesis examines the problems, both theoretical and practical, that arise when switching to cryptography resistant to quantum attacks. This thesis specifically examines how the NIST-selected algorithms, Kyber and Dilithium, are used in hybrid X.509 certificates that combine classical and post-quantum signatures.A test PKI environment was set up using OpenSSL-OQS and OpenXPKI to facilitate the testing process. Important PKI processes were examined in this setting, including TLS handshakes, certificate issuance, validation, and revocation. The results show that integrating PQC increases key and certificate sizes and also causes a moderate performance overhead. However, hybrid approaches offer a practical way to switch over. Lattice-based algorithms are particularly advantageous because they provide a strong balance of security, speed, and compatibility with existing systems. Using this information, a method was developed to help organizations gradually transition to a more secure system for managing their digital keys. This thesis connects advanced cryptography research with how businesses actually use it. It offers useful ideas and advice for companies getting ready for an age after quantum computing.
As quantum computing advances, current cryptographic protocols are increasingly vulnerable to quantum attacks, particularly those based on Public Key Infrastructure (PKI) like RSA or Elliptic Curve Cryptography (ECC). This paper presents a comprehensive review of Post-Quantum Cryptography (PQC) as a solution to protect digital systems in the quantum era. We provide an in-depth analysis of various quantum-resistant cryptographic algorithms, including lattice-based, code-based, hash-based, isogeny-based, and multivariate approaches. The review highlights the National Institute of Standards and Technology (NIST) PQC standardization process, highlighting key algorithms, such as CRYSTALS–Kyber, CRYSTALS–Dilithium, Falcon, and SPHINCS+, and discusses the strengths, vulnerabilities, and implementation challenges of the leading algorithms. In addition, we explore transition strategies for organizations, emphasizing hybrid cryptography to ensure backward compatibility during migration. This study offers key insights into the future of cryptographic standards and the critical steps necessary to prepare for the transition from classical to quantum-resistant systems.
The advent of quantum computing poses a significant threat to the foundational cryptographic algorithms that secure modern digital communications. [27]. Protocols such as HTTPS, digital certificates, and public key infrastructures (PKIs) heavily rely on cryptographic primitives like RSA, ECC, and Diffie-Hellman, which are vulnerable to quantum attacks—most notably Shor’s algorithm. [18]. This paper presents a comprehensive comparative analysis between classical cryptographic algorithms currently in widespread use and emerging post-quantum cryptographic schemes designed to withstand quantum adversaries. [24]. We review the cryptographic mechanisms underpinning modern internet security, outline the mathematical foundations of quantum attacks, and evaluate the security, performance, and implementation feasibility of quantum-resistant alternatives such as Kyber, Dilithium, and Falcon. [25]. Additionally, we assess the hybrid approaches currently being explored by institutions and tech companies to enable a smooth transition to post-quantum cryptography. [23]. By providing an in-depth comparison, this study aims to guide researchers, developers, and policymakers in understanding the critical implications of quantum computing on cryptographic infrastructures and the necessary steps for securing communications in the quantum era. [16].