Classical cryptographic primitives such as RSA or Diffie-Hellman key exchange are based on computationally difficult mathematical problems for the solution of which no efficient algorithms are known. However, with the advent of practical quantum computers, quantum algorithms can be used to easily solve these problems and break the security of these algorithms. For this reason, post-quantum algorithms are being rapidly developed, evaluated, and optimized to resist quantum attacks in the hope that they will be used in secure instant messaging protocols such as the Signal protocol, in addition to other secure network protocols. This literature review provides an overview of efforts to develop quantum-resistant primitives for secure instant messaging protocols, with a particular focus on the Signal protocol.
Classical cryptographic primitives such as RSA or Diffie-Hellman key exchange are based on computationally difficult mathematical problems for the solution of which no efficient algorithms are known. However, with the advent of practical quantum computers, quantum algorithms can be used to easily solve these problems and break the security of these algorithms. For this reason, post-quantum algorithms are being rapidly developed, evaluated, and optimized to resist quantum attacks in the hope that they will be used in secure instant messaging protocols such as the Signal protocol, in addition to other secure network protocols. This literature review provides an overview of efforts to develop quantum-resistant primitives for secure instant messaging protocols, with a particular focus on the Signal protocol.
The rapid growth of quantum computing poses a critical threat to classical cryptographic systems. That is due in large part to the fact that they represent efficient solutions for some of the most challenging mathematical problems such as integer factoring or finding discrete logarithms. Schemes currently in wide use including RSA, Diffie–Hellman, and elliptic curve cryptography are particularly susceptible to being attacked by quantum computers, using algorithms like Shor's Algorithm and Grover's Algorithm. The advent of post-quantum cryptography (PQC) provides a promising potential answer to providing longterm security from adversaries using quantum computing capabilities. This paper presents a comprehensive state-of-the-art review of various PQC techniques currently being researched, including lattice-based methods, code-based methods, multivariate methods, hash-based methods, and isogeny-based methods. key challenges that will need to be addressed include computational overhead, large key sizes and implementation complexity. Furthermore the study reviews the current standardization efforts by the National Institute of Standards and Technology related to PQC and discusses some of the very specific practical considerations that need to be considered before widely deploying these techniques. The paper concludes by a complete list of existing research challenges and proposed future work that will assist in the development of efficient and scalable systems that will resist attacks from quantum computers.
Because of Shor’s method, it is expected that quantum computers will have the capability to decipher current public key encryption methods. Consequently, there is a need to replace existing public key cryptography with quantum-resistant cryptography, also known as post-quantum cryptography (PQC) algorithms. In the last twenty years, significant progress has been made in the field of PQC research, leading to the creation of various algorithms that are proven to be resistant to quantum attacks. Several organizations responsible for standardization have already selected and are in the process of standardizing specific PQC algorithms.In popular instant messaging and voice-over IP applications like Signal, Facebook Messenger, and WhatsApp, the Signal Protocol provides end-to-end encryption (E2EE) and additional security features such as forward secrecy, future secrecy, authentication, asynchronous communication, and deniability. The protocol utilizes the ECDH Curve25519 key exchange and hash-based key derivation algorithms to accomplish this. However, the ECDH key exchange is vulnerable to attacks from quantum computers, which can compromise the security of contemporary cryptographic techniques by obtaining the corresponding public keys. Therefore, there is a need to replace the ECDH key exchange with a quantum-safe key exchange scheme that is resistant to attacks from quantum computers.In this context, the focus is on investigating post-quantum cryptography (PQC) that can provide robust security against quantum computing threats and proposing an end-to-end encryption scheme.
The Signal protocol can be considered state-of-the-art when it comes to secure messaging, but advances in quantum computing stress the importance of finding post-quantum resistant alternatives to its asymmetric cryptographic primitives. The aim is to determine whether existing post-quantum cryptography can be used as a drop-in replacement for the public-key cryptography currently used in the Signal protocol and what the performance trade-offs may be. An implementation of the Signal protocol using commutative supersingular isogeny Diffie-Hellman (CSIDH) key exchange operations in place of elliptic-curve Diffie-Hellman (ECDH) is proposed. The benchmark results on a Samsung Galaxy Note 8 mobile device equipped with a 64-bit Samsung Exynos 9 (8895) octa-core CPU shows that it takes roughly 8 seconds to initialize a session using CSIDH-512 and over 40 seconds using CSIDH-1024, without platform specific optimization. To the best of our knowledge, the proposed implementation is the first post-quantum resistant Signal protocol implementation and the first evaluation of using CSIDH as a drop-in replacement for ECDH in a communication protocol.
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].
Widely used communication and messaging protocols, e.g., TLS 1.3 and Signal, are insecure against an adversary with a quantum computer. We expect that post-quantum security will become mandatory for a new generation of cryptographic protocols in the nearest 10-15 years. The analysis of existing post-quantum secure cryptographic tools for key exchange, encryption and message authentication based on hard problems in codes, lattices, ring learning with errors and elliptic curve isogenies revealed their advantages and drawbacks. In particular, we conclude, that the main threat to communication and messaging protocols is only pre-quantum security of currently used Diffie-Hellman key exchange protocols. We summarize efficiency and safety results for each class of post-quantum cryptographic schemes and present an experimental implementation of isogeny-based Diffie-Hellman-like key exchange protocol as an illustration of their applicability.
Abstract It is viewed as revolutionary technology, offering incredible potential in terms of computing power within different scientific and industrial sectors. Quantum computers provide remarkable computing power; however, they also present significant security risks to existing public-key cryptography systems used to secure digital communication, online banking systems, government, medical applications, cloud computing systems, and IoT systems. Security of commonly used encryption schemes like RSA, DH, and ECC depends on mathematical problems that are impossible for classical computers to solve but can be easily resolved with the help of powerful enough quantum computers by using Shor’s algorithm. Furthermore, Grover’s algorithm makes exhaustive search attacks much faster, thus effectively lowering the security level of symmetric encryption schemes since it provides the speed-up for brute-force attacks. Post-Quantum Cryptography (PQC) turned out to be an effective and scalable method to protect digital data from attacks using quantum computing. In contrast to quantum cryptography, which requires a special quantum communication channel, PQC uses classical cryptographic algorithms that cannot be broken down by either classical or quantum computer due to certain mathematical problems. This research paper offers an extensive exploration of post-quantum cryptography through the analysis of the development of quantum computing, weaknesses of current cryptographic techniques, and mathematics behind quantum-resistant algorithms. Moreover, this paper explores the major classes of PQC techniques such as lattice-based, code-based, hash-based, multivariate, and isogeny-based cryptography and provides details about their security and application. Moreover, the report gives an overview of the NIST Post-Quantum Cryptography Standardization Project and analyzes recent standardizations of quantum-proof algorithms to be utilized in future digital infrastructures. Keywords: Post-Quantum Encryption, Quantum Security, Quantum-Proof Public-Key Cryptography, Lattice-Based Security Protocols, ML-KEM Key Encapsulation Mechanism, ML-DSA Digital Signature Algorithm, NIST Post-Quantum Cryptography, Contemporary Cybersecurity, Secure Communications, Cryptographic Algorithms.