COMPARISON OF THE PERFORMANCE OF THE POST-QUANTUM CRYSTALS-KYBER ALGORITHM AND CLASSICAL RSA SCHEMES IN DECENTRALIZED COMMUNICATION SYSTEMS

Abstract

The rapid development of quantum computing over the past decade has created unprecedented challenges for modern cryptography. The emergence of the quantum Shor algorithm theoretically allows solving data protection problems in the network in polynomial time, making existing protection standards vulnerable. The introduction of new standards requires additional justification, which can be performed by comparing the computational complexity and performance of post-quantum algorithms with existing analogues. The task is especially relevant for real-time systems. To solve the task, we initiated a comparative benchmarking of the CRYSTALS-Kyber-1024 algorithm (security level 5, the highest level according to the NIST classification) against the classical RSA-2048 and RSA-1024 schemes. The obtained data refute the widespread belief that post-quantum cryptography is significantly slower than classical cryptography. On the contrary, the Kyber-1024 algorithm turned out to be 4.28 times faster than the modern RSA-2048 standard. This means that replacing RSA with Kyber in session establishment protocols not only increases the system's resistance to quantum attacks, but also significantly reduces the computational load on the server and client devices, saving up to 76.6% of time for cryptographic operations. Compared to the outdated and insecure RSA-1024, Kyber-1024 is slower, but given RSA-1024's catastrophic vulnerability to modern attacks, this characteristic is a perfectly acceptable trade-off for ensuring quantum stability. Graphs of the dependence of execution time and throughput on the data size showed the stability of the Kyber algorithm. Thus, post-quantum cryptography has reached a level of maturity sufficient for mass implementation in high-performance systems. The obtained data allow us to recommend the CRYSTALS-Kyber-1024 algorithm as the main standard for the development of new decentralized messengers and secure communication systems in Ukraine.