The proposed article is devoted to the investigation of quantum key distribution protocols. The idiosyncrasy of this theme lies within the truth that present day strategies of key distribution, which utilize classical computing at their center, have critical downsides, in contrast to quantum key distribution. This issue concerns all sorts of calculations and frameworks for scrambling mystery data, both symmetric encryption with a private key and deviated encryption with an open key. A case is that in a communication channel ensured by quantum key distribution, it is conceivable to distinguish an interceptor between two legitimate organize substances utilizing the standards laid down in quantum material science at the starting of the final century. Standards and hypotheses such as the Heisenberg guideline, quantum trap, superposition, quantum teleportation, and the no-cloning hypothesis. The field of ponder of this theme may be a promising and quickly creating zone within the field of data security and data security. There are as of now made commercial items with the usage of a few of the quantum key dispersion conventions. Numerous of the made items are utilized in different circles of human movement. The significance of applying quantum key distribution conventions beneath perfect conditions without taking into consideration blunders within the frame of quantum clamor is analyzed. The usage of three quantum key distribution conventions is illustrated, as well as the comes about of the appearance of keys and the likelihood of event of each of them. The purpose of the article is pointed at analyzing and investigating quantum key distribution conventions. The article examines the points of interest and impediments of the BB84, B92, and E91 quantum key distribution conventions.

Conventional public-key cryptographic systems are increasingly threatened by advances in quantum computing, accelerating the need for robust post-quantum cryptographic solutions. Among these, Falcon, a compact lattice-based digital signature scheme, has emerged as a leading candidate in the NIST post-quantum standardization process due to its efficiency and theoretical security grounded in hard lattice problems. This work introduces Falcon-M, a modified version of the Falcon algorithm that significantly reduces implementation complexity. It does so by replacing Falcon’s intricate trapdoor-based key-generation mechanism with a simplified approach that utilizes randomized polynomial Gaussian sampling and fast Fourier transform (FFT) operations. Falcon-M incorporates SHA-512 hashing and discrete Gaussian sampling to preserve cryptographic soundness and statistical randomness while maintaining the core structure of Falcon’s signing and verification processes. We formally specify the Falcon-M algorithm, provide an updated pseudocode, and offer a comparative analysis with the original Falcon in terms of algorithmic complexity, security assumptions, and implementation overhead. Additionally, we present formal lemmas and theorems to ensure correctness and define theoretical bounds on forgery resistance. Although Falcon-M does not rely on a formal cryptographic trapdoor, we demonstrate that it achieves strong practical security based on assumptions related to the Short Integer Solution (SIS) problem. Falcon-M is thus well-suited for lightweight post-quantum applications, particularly in resource-constrained environments, such as embedded systems and Internet-of-Things (IoT) platforms.

A model of an automated system for secure cross-border information exchange is considered. This automated system presents as a complex of the following modules which ensure the information security: data encryption, an electronic digital signature (EDS), access control to the stored information based on two-factor authentication, resolution of possible conflict situations. In this paper, models of two modules for an automated system are described: the electronic digital signature and access control to information based on two-factor authentication. The mathematical model of the formation and verification of the digital signature is described in detail. The phased software implementation of this model with the analysis of the results is described. The two-factor authentication algorithm based on the authenticator program and a mobile phone is considered. A secret string generator based on the method of exhaustive search was carried out. A generator of trigonometric functions is described, which is used to calculate a one-time password. The phased software implementation of this model is given. The analyzed results of the algorithm are presented.

In the modern world, medical data leakage has many external and internal threats. Information systems of medical organizations are constantly subject to various types of cyber-attacks and unauthorized penetration attempts, which leads to the publication of patient medical data online. Existing authentication schemes using blockchain technologies in medical organization systems ensure the integrity of medical data and secure access to patient data. However, one of the serious reasons for unauthorized access to the healthcare system is the human factor, which manifests itself in a negligent attitude towards account security, non-compliance with the rules and policies of information security, and transferring to third parties personal login details to the information system of a medical organization. This paper proposes a solution to this problem through an improved two-step authentication scheme using cloud technology and blockchain. The combined use of cloud technologies and blockchain is a distinctive feature of the proposed authentication scheme since it provides two levels of protection: 1) two-step authentication, the second stage of which includes biometrics through a mobile application. It prevents unauthorized access to the system by third parties; 2) cloud encryption keys for decrypting medical data, which are also accessed through the user's biometrics. The practical part of the paper includes the implementation of biometric login in Python using the OpenCV library. As a result of the practical part, unique fingerprint samples were obtained. The biometric user verification algorithm is designed for a mobile application, which we plan to implement in the future

The object of this research is the security of communication networks, particularly in decentralized, multi-user environments where robust data protection and integrity are critical. The issue under discussion is the rising vulnerability of conventional cryptography systems resulting from ever complex cyberattacks and the expected risks presented by quantum computing possibilities. The development of a QKD protocol employing quantum superposition to improve data security and resilience against both present and future quantum-based cyber-attacks is demonstrated by the achieved results of this work. Achieving scalability and autonomous eavesdropping detection, this protocol lets several communication nodes securely exchange randomly produced keys without centralized management. A quick analysis of the results reveals that main elements influencing the great durability, security, and adaptability of the protocol are quantum superposition and its distributed character. Without centralized authority, the characteristics of the obtained results – especially the use of optical components, detectors, and quantum sources in conjunction with classical communication channels – solve the problem of ensuring data confidentiality and integrity in a multi-user environment. This protocol's practical reach covers safe communication applications in both public and private sectors, therefore addressing situations calling for strong data protection against modern cyberattacks. Conditions for practical application include settings like government, financial, or health-related interactions when safe information flow is crucial. This QKD system offers a future-ready security solution for high-stakes environments and represents notable advancement toward protecting data from quantum and conventional attacks

The object of the study is authentication systems in security-critical environments, especially in healthcare. The addressed problem is the absence of comprehensive frameworks that integrate both threat data and user-centric factors for real-world method comparison. This study develops and validates a novel evaluation model for assessing the empirical effectiveness of user authentication methods. The proposed model integrates probabilistic threat modeling, usability data, and weighted multi-criteria analysis to generate context-sensitive effectiveness scores, thereby supporting informed decision-making. Twelve authentication methods were assessed using three criteria: security (resistance to cyber threats), usability (user convenience), and use frequency (real-world adoption). Security coefficients (K2) were computed from threat statistics, while usability and adoption metrics were based on a healthcare survey (n = 70). Weighted normalization (ws = 0.4, wu = 0.3, wf = 0.3) produced overall effectiveness scores (E). The most effective methods were mobile devices (E = 30.915), PIN codes (E = 30.252), and fingerprint authentication (E = 29.235), offering an optimal balance of security and acceptance. Graphical passwords (E = 6.132) and iris scans (E = 7.245) scored lowest due to poor usability and limited adoption. The model’s feature lies in its holistic integration of threat exposure and empirical user data, along with adaptability to organizational requirements and visual interpretability. This feature distinguishes it from single-dimensional or static assessment models