Oleksandr Pidpalyi, Олександр Романов, Larysa Globa, Антон Романов · 6 authors
The subject matter of the article is the iTZBEI (Integrated Trust–ZTA–Blockchain SDN Efficiency Index) – a novel composite metric for quantitative security assessment of software-defined networks (SDN) integrating Zero Trust Architecture (ZTA) and Blockchain technologies. The relevance of the research is determined by the fact that the centralized SDN control model generates critical vulnerabilities, including DDoS attacks, unauthorized routing manipulation, and insider threats – for which no unified quantitative evaluation framework currently exists. The study introduced a formalized aggregated security metric that enables continuous monitoring and comparative assessment across all components of the SDN–ZTA–Blockchain architecture. The tasks to be solved include: (1) identification of principal SDN attack vectors; (2) formalization of a transaction-processing algorithm covering the full access lifecycle; (3) definition of nine local security indicators; and (4) construction of the iTZBEI index with justified weighting coefficients. The methods used combine mathematical formalization of access control processes, cryptographic transaction verification, and experimental emulation of attack scenarios in a Mininet–OpenDaylight–Hyperledger Fabric environment. Conclusions. The obtained results of the article consist in the development of a functional algorithm that performs dynamic verification of user requests, makes adaptive authorization decisions according to the principles of least privilege, and records these decisions in an immutable distributed ledger. A metrics system is proposed, including local indicators such as the Continuous Authorisation Integrity Score (CAIS), the Blockchain Audit Integrity Score (BAIS), and the Local Policy Integrity (LPI). On this basis, the generalized Integrated Trust and Zero-Trust Blockchain Evaluation Index (iTZBEI) is described as an aggregated metric for comparative evaluation and continuous monitoring of the network’s security state. Scientific novelty. This study introduces a unified SDN + ZTA + Blockchain framework for network security, formalizes a transaction-level algorithm that directly links access decisions with distributed audit procedures, and proposes the iTZBEI metric as the first integral indicator for evaluating the integration’s effectiveness in dynamic network environments.
The article provides a scientific substantiation of conceptual proposals for shaping the architecture of a promising state air and missile defense (AMD) system based on the implementation of the Integrated Air and Missile Defense (IAMD) concept. The study addresses the urgent need to modernize existing air defense structures in response to the transformation of modern warfare. The subject of the research is the structural, organizational, and technical parameters of airspace defense systems. The topic encompasses the transition from isolated, traditional defense lines to a unified, network-centric "System of Systems". The primary purpose of the work is to develop a comprehensive theoretical model and practical guidelines for building an adaptive, multi-layered, and resilient national IAMD system capable of neutralizing current and emerging combined aerial threats. The research methodology is based on an integrated combination of several scientific approaches. The systems approach and system analysis were utilized to view the IAMD framework as a complex multi-level structure operates within a single information and communication space (including reconnaissance, command and control, engagement, and electronic warfare subsystems). The comparative-historical method was applied to analyze the evolution of AMD concepts and the practical experience of deploying defense tools during the full-scale Russian-Ukrainian war. The generalization method enabled a transition from assessing specific technical parameters of various weapons to formulating a holistic integration model. Military-strategic forecasting was used to identify global trends in aerial attack technologies. Additionally, Open-Source Intelligence (OSINT) methodologies were applied to gather empirical data on enemy tactics, strike consequences, and techno-tactical trends. The study provides a rigorous terminological analysis and establishes a unified conceptual apparatus detailing the operational logic of modern airspace defense. Key operational-tactical and technical requirements for the IAMD infrastructure have been formalized. The paper introduces the concept of an "Open IAMD Architecture", which relies on standardized APIs, unified protocols, and a centralized national software Command and Control (C2) core scalable from the battalion to the national level. The integration of the "Any Sensor, Best Shooter" principle is defined as a primary mechanism to merge diverse sensors, fire units, and hybrid systems (such as FrankenSAM) into a singular combat field. Furthermore, the study formalizes the necessity of shifting toward quantitative Key Performance Indicators (KPIs) and implementing Decision Support Systems (DSS) combined with regional digital twins for advanced scenario modeling. The authors conclude that the proposed theoretical framework successfully shifts the focus of airspace defense from passive monitoring to dynamic, high-precision threat liquidation. The system must maintain decentralized resilience, allowing individual air defense cells to operate autonomously even during network disruptions. The scope of application for these results includes military command and control bodies, defense industry planning agencies, state bodies responsible for critical infrastructure protection, and academic institutions engaged in designing promising military hardware, simulation environments, and strategic defense doctrines.
Ігор Григорійович Дзеверін, Володимир Валерійович Коваль, Борис Степанович Москалик
The article provides a scientific substantiation of conceptual proposals for shaping the architecture of a promising state air and missile defense (AMD) system based on the implementation of the Integrated Air and Missile Defense (IAMD) concept. The study addresses the urgent need to modernize existing air defense structures in response to the transformation of modern warfare. The subject of the research is the structural, organizational, and technical parameters of airspace defense systems. The topic encompasses the transition from isolated, traditional defense lines to a unified, network-centric "System of Systems". The primary purpose of the work is to develop a comprehensive theoretical model and practical guidelines for building an adaptive, multi-layered, and resilient national IAMD system capable of neutralizing current and emerging combined aerial threats. The research methodology is based on an integrated combination of several scientific approaches. The systems approach and system analysis were utilized to view the IAMD framework as a complex multi-level structure operates within a single information and communication space (including reconnaissance, command and control, engagement, and electronic warfare subsystems). The comparative-historical method was applied to analyze the evolution of AMD concepts and the practical experience of deploying defense tools during the full-scale Russian-Ukrainian war. The generalization method enabled a transition from assessing specific technical parameters of various weapons to formulating a holistic integration model. Military-strategic forecasting was used to identify global trends in aerial attack technologies. Additionally, Open-Source Intelligence (OSINT) methodologies were applied to gather empirical data on enemy tactics, strike consequences, and techno-tactical trends. The study provides a rigorous terminological analysis and establishes a unified conceptual apparatus detailing the operational logic of modern airspace defense. Key operational-tactical and technical requirements for the IAMD infrastructure have been formalized. The paper introduces the concept of an "Open IAMD Architecture", which relies on standardized APIs, unified protocols, and a centralized national software Command and Control (C2) core scalable from the battalion to the national level. The integration of the "Any Sensor, Best Shooter" principle is defined as a primary mechanism to merge diverse sensors, fire units, and hybrid systems (such as FrankenSAM) into a singular combat field. Furthermore, the study formalizes the necessity of shifting toward quantitative Key Performance Indicators (KPIs) and implementing Decision Support Systems (DSS) combined with regional digital twins for advanced scenario modeling. The authors conclude that the proposed theoretical framework successfully shifts the focus of airspace defense from passive monitoring to dynamic, high-precision threat liquidation. The system must maintain decentralized resilience, allowing individual air defense cells to operate autonomously even during network disruptions. The scope of application for these results includes military command and control bodies, defense industry planning agencies, state bodies responsible for critical infrastructure protection, and academic institutions engaged in designing promising military hardware, simulation environments, and strategic defense doctrines.
The paper proposes an extended quality assessment model for Distributed Ledger Technology platforms, referred to as DLT-QM, developed on the basis of the ISO/IEC 25010 standard while considering the architectural and operational specifics of decentralized and blockchain-based systems. The relevance of the study is determined by the rapid development of digital technologies and the growing adoption of DLT platforms in finance, e-government, logistics, IoT ecosystems, and enterprise information systems, alongside the absence of a unified formalized approach for comprehensive quality assessment of such platforms. The study analyzes the applicability of ISO/IEC 25010 charac-teristics to DLT-oriented software systems and identifies a set of DLT-specific quality attributes reflecting the unique properties of distributed ledger environments, including decentralization level, consensus reliability, transaction finality, auditability, trust model, interoperability, and on-chain/off-chain balance. For each characteristic, mathematical metrics are formalized to support multicriteria quality assessment and optimization of architectural decisions in software engineering tasks. The integral quality indicator QDLT is defined as a weighted combination of the traditional ISO/IEC 25010 component and a DLT-specific component, enabling the adaptation of the model to various application scenarios. The proposed model is validated using four representative DLT platforms: Hyperledger Fabric, Ethereum, Corda, and Polygon. The obtained results confirm the existence of structural trade-offs between decentralization, performance, security, and interoperability in modern distributed systems. Furthermore, a scenario-oriented application methodology is developed, including a procedure for determining weighting coefficients depending on the application domain, such as financial consortium systems, e-government infrastructures, and IoT supply chain environments. The practical significance of the research lies in the development of a formalized decision-support instrument for selecting DLT platforms in the design and implementation of modern software systems and digital services. Keywords: blockchain, distributed ledger technology, DLT platforms, decentralized systems, distributed systems, information technologies, digital technologies, software engineering.
Юлія Гусєва, Ігор Чумаченко, Іван Некрасов, Ілля Худяков · 5 authors
The subject of this study is the processes of ensuring transparency, accountability, and data integrity in project portfolio management systems based on distributed ledger technologies. The objective of this work is to develop a conceptual model, the Blockchain Portfolio Governance Model (BPGM), to enhance the transparency, integrity, and manageability of strategic portfolio management processes. Objectives: to develop a multi-level model architecture that combines traditional management cycles with cryptographic event logging mechanisms; to formalize management decisions as distributed ledger objects using asymmetric cryptography; to propose a comprehensive management quality assessment metric that accounts for both technical integrity and procedural discipline; to validate the model through simulation modeling of business processes. Research methods: systems analysis, methods of mathematical and simulation modeling in the Bizagi Modeler environment, asymmetric encryption, and hashing algorithms to ensure data integrity in distributed networks. Results. This paper proposes and justifies the architecture of the Blockchain Portfolio Governance Model, comprising five levels: governance, data aggregation, decision formalization, cryptographic integrity, and audit. A mathematical framework for event logging has been developed, where each decision is signed using the ECDSA digital signature algorithm. A new comprehensive metric has been introduced – the Portfolio Governance Compliance Index – which enables the detection of "shadow" management actions by comparing the number of requests initiated in external systems with the number of validated transactions on the blockchain. A series of simulation experiments demonstrated that implementing Proof-of-Authority consensus algorithms in a corporate network introduces negligible time delays (less than 1% of the total cycle), while the majority of the process time is spent on expert analysis. Conclusions: The application of the BPGM model enables transforming subjective portfolio management into a transparent, algorithmic process. The proposed solution ensures the creation of a «single source of truth» for all stakeholders, significantly simplifies audit procedures, and enhances the organization’s institutional reliability without compromising its operational efficiency.
Yuliia Husieva, Igor Chumachenkо, I. B. Nekrasov, Illia Khudiakov · 5 authors
The subject of this study is the processes of ensuring transparency, accountability, and data integrity in project portfolio management systems based on distributed ledger technologies. The objective of this work is to develop a conceptual model, the Blockchain Portfolio Governance Model (BPGM), to enhance the transparency, integrity, and manageability of strategic portfolio management processes. Objectives: to develop a multi-level model architecture that combines traditional management cycles with cryptographic event logging mechanisms; to formalize management decisions as distributed ledger objects using asymmetric cryptography; to propose a comprehensive management quality assessment metric that accounts for both technical integrity and procedural discipline; to validate the model through simulation modeling of business processes. Research methods: systems analysis, methods of mathematical and simulation modeling in the Bizagi Modeler environment, asymmetric encryption, and hashing algorithms to ensure data integrity in distributed networks. Results. This paper proposes and justifies the architecture of the Blockchain Portfolio Governance Model, comprising five levels: governance, data aggregation, decision formalization, cryptographic integrity, and audit. A mathematical framework for event logging has been developed, where each decision is signed using the ECDSA digital signature algorithm. A new comprehensive metric has been introduced – the Portfolio Governance Compliance Index – which enables the detection of "shadow" management actions by comparing the number of requests initiated in external systems with the number of validated transactions on the blockchain. A series of simulation experiments demonstrated that implementing Proof-of-Authority consensus algorithms in a corporate network introduces negligible time delays (less than 1% of the total cycle), while the majority of the process time is spent on expert analysis. Conclusions: The application of the BPGM model enables transforming subjective portfolio management into a transparent, algorithmic process. The proposed solution ensures the creation of a «single source of truth» for all stakeholders, significantly simplifies audit procedures, and enhances the organization’s institutional reliability without compromising its operational efficiency.
This paper develops a document management system model intended for environments in which the integrity of document history, control of the document lifecycle, and the possibility of independent verification of performed operations are critically important. The relevance of the study is determined by the fact that traditional electronic document management systems mainly rely on centralized event logs and application logic, which does not eliminate the risks of retrospective modification of document history and a reduction in its evidential value. The aim of the work is to construct a document management system model in which the integrity of document history is ensured through a cryptographically verifiable chain of document states and the recording of evidential event attributes in a permissioned distributed ledger. The proposed model combines architectural and formal levels of system representation. At the architectural level, the user, application, evidential, and content layers are distinguished. At the formal level, a document is represented as a sequence of cryptographically linked states, in which each new state contains the state hash, metadata, timestamp, content hash, and a reference to the previous state, thus ensuring the integrity and traceability of the entire document history. To implement the evidential layer, a smart contract for registering document states and a permissioned distributed ledger based on Hyperledger Besu are used. Experimental validation of the model was carried out on a local testbed using the QBFT consensus mechanism, external storage, and software modules for generating and fully verifying document history. The experimental results confirmed the ability of the model to detect retrospective changes in content, metadata, signatures, and temporal attributes, to localize the first compromised state, and to provide near-linear growth in full verification time as the length of the state chain increases. Comparative evaluation against centralized logging demonstrated the advantage of the proposed approach in terms of tamper detection, localization of violations, and independent verifiability of results. The practical significance of the work lies in the possibility of using the proposed model as a basis for building corporate document management systems.
The paper investigates the problem of ensuring confidentiality in authentication processes within enterprise information-intelligent systems under increasing cybersecurity threats and growing requirements for data protection. The introduction substantiates the relevance of modern cryptographic approaches that minimize the transmission of sensitive information during user authentication. The literature review analyzes approaches to constructing zero-knowledge proofs, which enable verification of a statement without revealing secret data, including succinct non-interactive arguments of knowledge, transparent scalable arguments of knowledge, and compact proof systems without trusted setup. Their cryptographic properties, trust assumptions, scalability, and computational characteristics are examined. In the methodology section, an adaptive authentication model is proposed, based on the integration of cryptographic proofs with risk assessment mechanisms and contextual access analysis. A formal decision-making model for access control is developed, taking into account user parameters, environmental characteristics, and threat levels, enabling dynamic selection of the proof type depending on the current risk level. An authentication algorithm is designed, including stages of identification, context evaluation, proof generation, and verification. In the results section, a comparative analysis of different types of zero-knowledge proofs in enterprise systems is conducted, evaluating their impact on performance, security level, and resistance to attacks. It is shown that the adaptive approach ensures a balance between cryptographic strength and computational efficiency. The conclusions justify the feasibility of implementing the proposed model as part of modern continuous access verification concepts and as a means of improving enterprise information security.
Introduction. The article examines the role of fifth-generation (5G) networks in the development of logistics systems based on the Internet of Things (IoT) technology. The integration of 5G, IoT, and edge computing forms the technological foundation of Logistics 4.0, smart cities, and digital supply chains. Purpose. The purpose of the study is to substantiate the possibilities and advantages of using 5G networks in logistics by analyzing their interaction with IoT and edge computing, as well as to assess the impact of 5G on the efficiency of supply chain management. Research Methods. The study employs methods of systems and comparative analysis, generalization of scientific sources, tabular comparison of the technical characteristics of 4G and 5G networks, and a logical-analytical method to identify the key areas of 5G application in logistics. Results. It has been established that the implementation of 5G in logistics systems based on the Internet of Things (IoT) provides a new level of supply chain management. A comparative analysis of the technical characteristics of 4G and 5G networks demonstrates a significant reduction in data transmission latency, a substantial increase in bandwidth, and the possibility of massive connectivity of IoT devices within local and global logistics networks. This creates prerequisites for continuous data collection, transmission, and processing of large volumes of data in real time. It is proven that the integration of 5G with edge computing enables the decentralization of the IT architecture of logistics systems, reduces the load on central servers, and minimizes risks associated with long-distance data transmission. The key areas of application of 5G technology in logistics are identified. It is established that the use of 5G in cargo monitoring systems ensures highly accurate tracking of transportation parameters, while warehouse logistics automation based on 5G creates conditions for the efficient operation of robotic complexes, autonomous vehicles, and drones. Conclusion. 5G networks constitute a basic infrastructure for the formation of intelligent, adaptive, and resilient logistics systems. At the same time, the effective implementation of 5G requires a comprehensive consideration of cybersecurity, infrastructural, and organizational risks, which is a prerequisite for enhancing the competitiveness of logistics networks in the digital economy.
Євген Олександрович Живило, Юрій Володимирович Кучма
Formulation of the problem in general. The purpose of the article is to develop a multi-agent model of adaptive trust for decentralised confidential systems, capable of ensuring the integrity and reliability of computing processes in the presence of adaptive attacks on network nodes. Research methods. During the research, analysis and synthesis methods were used to study approaches to the construction of multi-agent systems and trust management mechanisms in decentralised environments. The method of system and simulation modelling was used to develop a multi-agent model of adaptive trust and to study its behaviour under attacks on the integrity of computing processes. Experimental and comparative methods enabled evaluation of the proposed approach's effectiveness and justification of its advantages over static trust models. Literature review. Literary analysis shows that modern models of trust in decentralised systems are based on the integration of dynamic adaptive mechanisms, AI algorithms, and cryptographic protocols, which allow for increased cyber resilience and data integrity. At the same time, questions remain open about the scalability of models, the optimisation of adaptation parameters, and the integration of national and European regulatory approaches into practical systems, which provide a scientific perspective for the development of multi-agent models of adaptive trust. Research results. The article formalises attacks on the integrity of computing processes and develops a multi-agent model of adaptive trust for decentralised confidential systems based on Bayesian updating and evolutionary adaptation of strategies. The results of the simulation experiments confirmed that the proposed model provides high resistance to attacks, rapid stabilisation of agent confidence levels and an effective balance between security, privacy and performance. Research novelty. The work improves approaches to trust formation in decentralised systems by integrating models of multi-agent interaction and stochastic game theory, in which trust is modelled as an evolutionary process under conditions of incomplete information. Well-known Bayesian models of trust have been expanded by combining Bayesian belief update mechanisms with reinforcement learning algorithms, ensuring dynamic adaptation of agent behaviour to variable and targeted attacks on the integrity of computational processes. The mechanism for correcting agents' strategies has been clarified, extending classic game models of trust to decentralised, confidential systems without centralised control, thereby increasing their resistance to adaptive threats. Theoretical and practical significance. The study expands theoretical approaches to the formation of adaptive trust in decentralised systems and integrates Bayesian updating with reinforcement learning algorithms. In practice, the model increases resistance to integrity attacks and ensures the confidentiality of data exchange, enabling the adaptive development of secure platforms for federated learning, Web3, and IoT. Conclusion and future work. The proposed model of adaptive trust in decentralised systems, integrating Bayesian updating, behavioural indicators, and reinforcement learning, ensures agent self-adaptation and increases resistance to attacks on data integrity under conditions of incomplete information. Simulation experiments confirmed the model's effectiveness in balancing security, privacy, and the transparency of interaction, opening the way for integration into Zero Trust Architecture and the development of intelligent, next-generation trust systems.
Стаття присвячена створенню мультимодальної системи прогнозування Bitcoin, яка об’єднує традицiйнi ринковi показники з аналiзом новин через нейромережi LSTM та GRU. Завдяки використанню GDELT та моделi FinBERT авторам вдалося видiлити вплив геополiтики й фiнансiв на крипторинок, що пiдняло точнiсть прогнозiв на 15-хвилинних iнтервалах з 53,2% до вражаючих 77,8%. Головна особливiсть пiдходу — механiзм щотижневого адаптивного донавчання, який рятує модель вiд застарiвання, та виявлення 30-хвилинної затримки, з якою макроекономiчнi новини реально вiдображаються на цiнi. Наукова новизна зосереджена на алгоритмi автоматичного коригування ваг мережi, що дозволяє системi самостiйно пiдтримувати актуальнiсть в умовах хаотичного ринку.
Запропоновано середовище імітаційного моделювання явища максимально екстрактованої вигоди MEV (англ. Maximal Extractable Value), реалізоване мовою програмування Python із використанням бібліотеки Gymnasium, яке відтворює взаємодію сховища-мемпулу, конструювальника блоків, агента MEV-екстрактора та AMM-пулу децентралізованої біржі. Формально середовище описано як розширений та частково спостережуваний процес прийняття рішень, у межах якого агент взаємодіє з дискретно-часовою моделлю епізодів, що відображає послідовність надходження транзакцій, побудови блоків і виконання swap-операцій обміну на децентралізованій крипто-біржі. Для моделювання адаптивної поведінки агента використано методи навчання з підкріпленням, а для кількісного аналізу втрат користувачів застосовано контрфактичний підхід до оцінювання, що дає змогу порівнювати результати виконання транзакцій у різних режимах впорядкування за однакових вхідних умов. У дослідженні використано раніше описаний авторами метод зменшення негативних ефектів MEV-екстракції на основі логічних часових міток Лампорта, який реалізує локальне причинно-наслідкове впорядкування транзакцій у межах окремого смарт-контракту без модифікації глобального механізму консенсусу мережі блокчейн Ethereum. Для оцінювання практичної ефективності цього підходу сформовано три сценарії моделювання: базовий сценарій без систематичної MEV-атаки для визначення накладних витрат застосування механізму захисту, сценарій систематичної sandwich-атаки для аналізу та здатності методу зменшувати втрати користувачів та обмежувати можливості MEV-екстрактора, а також сценарій параметричного аналізу, спрямований на дослідження компромісу між рівнем захисту та "вартістю" його застосування. Отримані результати показали, що запропонований метод MEV-захищеного впорядкування може зменшувати цінові втрати користувачів від sandwich-атак і, водночас, впливати на частоту відхилення транзакцій та пов'язані комісійні витрати, що вказує на наявність керованого компромісу між ефективністю захисту та накладними витратами його використання. Практична цінність роботи полягає у створенні відтворюваного середовища імітаційного моделювання для дослідження стратегічної поведінки MEV-агентів і перевірки механізмів зменшення негативних наслідків MEV у контрольованих умовах, що може бути використано для подальшого аналізу безпеки протоколів децентралізованих фінансів та проєктування нових методів впорядкування транзакцій.
The subject of research covers the theoretical, methodological, and applied aspects of implementing blockchain technology and smart contracts into microgrid management systems, as well as the automation processes of energy resource exchange between participants of a distributed energy system. The purpose of this work is to investigate the methodological foundations for the application of blockchain and smart contracts in microgrids through the analysis of contemporary scientific research, systematization of approaches to consensus algorithm implementation, classification of smart contracts by application areas, and experimental verification of the proposed solutions. To achieve this goal, the following tasks were addressed: analyzing existing microgrid architectures and management methods; conducting a comparative analysis of consensus algorithms (PoW, PoS, PoA, PBFT, RAFT, etc.) regarding their applicability in private and public energy grids; developing a classification of smart contracts based on their application areas; and investigating software tools for implementing decentralized applications. Research Methods. The study employs system analysis methods to investigate microgrid architecture, comparative analysis to evaluate the efficiency of consensus algorithms, and classification methods for grouping smart contracts. For the practical part, computer modeling and experimental verification methods were used: smart contract development in Solidity, testing in the Remix IDE environment, and simulation of a local blockchain network using the Hardhat toolkit. Research results. The research systematized the methodological foundations for integrating blockchain into microgrids. It was determined that hybrid or private consensus models are most effective for energy trading within local communities. A classification of smart contracts was developed and justified, covering four levels: energy trading, monitoring, distributed management, and cybersecurity. The practical result is the implementation of the EnergyTrading smart contract, which successfully automates the process of listing offers and purchasing electricity, as confirmed by experiments in a local environment. The implementation of smart contracts allows for the creation of a reliable P2P platform for electricity trading without intermediaries, increasing economic efficiency for households. The functionality of the automated settlement mechanism was experimentally confirmed. At the same time, key challenges were identified: the limited scalability of existing blockchain solutions and the need to improve cyber defense against vulnerabilities in contract code. Further development requires adaptation of the legislative framework and modernization of the hardware components of energy grids.
У статті запропоновано модель зберігання та верифікації персональних даних на основі технології розподіленого реєстру (блокчейну), орієнтовану на підвищення довіри до цифрових сервісів. Розглянуто архітектуру системи, що включає модулі збору, шифрування, запису метаданих у блокчейн, контроль доступу за допомогою смарт-контрактів і алгоритми перевірки цілісності даних без їх розкриття. Описано формат блоку для запису, модель управління правами доступу на основі мультипідпису та реалізацію політик доступу у вигляді смарт-контрактів. Проведено експериментальне тестування продуктивності моделі в середовищі Hyperledger Fabric із використанням типових сценаріїв, зокрема перевірки освітніх і медичних записів, електронної ідентифікації тощо. Отримані результати свідчать про високу швидкість верифікації, низьке ресурсне навантаження та масштабованість. Запропоноване рішення демонструє наукову новизну завдяки поєднанню механізмів zero-knowledge proof, гнучких політик доступу й інтеграції з зовнішніми цифровими платформами через API. Розроблена модель може бути основою для створення довірених цифрових інфраструктур у сфері електронного врядування, охорони здоров’я та фінансів.
The rapid penetration of decentralized financial mechanisms into the structure of Ukraine's cryptocurrency market, where the volume of DeFi transactions consistently exceeds that of centralized platforms, highlights the need for effective tools to maintain the instant solvency of lending protocols during periods of sharp price fluctuations in digital assets. The purpose of this article is to systematize liquidity risks in decentralized financial systems, conduct a comparative assessment of algorithmic strategies for their minimization, and identify ways to enhance the stress resilience of protocols. The methodological basis of the study consists of a taxonomic analysis for classifying types of risks, a comparative analysis of the effectiveness of key liquidity management strategies, economic-mathematical modeling of cascading liquidation processes, and a correlation analysis of the relationship between the magnitude of cryptoasset price declines and the frequency of protocol failures. The empirical basis consists of on-chain data on the transaction activity of leading DeFi protocols for the period 2024–2026. The results show that hybrid configurations–which combine dynamic interest rate regulation with overcollateralization and decentralized oracle networks–demonstrate the highest resilience to extreme volatility. It was found that increasing collateral requirements proportionally reduces the probability of cascading liquidations, but simultaneously limits the protocol's capital efficiency, highlighting the need to optimize these parameters. It has been established that compositional links between protocols create a domino effect: a local liquidity shortage in one pool can trigger a chain of forced liquidations in adjacent systems within a critically short time frame. The scientific novelty lies in the development of a typologized scheme for neutralizing liquidity threats, which, unlike existing ones, integrates sentinel oracle, execution liquidation, and reserve insurance instruments into a unified protocol risk management system. The method for estimating margin call thresholds has been improved to account for the historical volatility of specific cryptoassets. The practical significance of the obtained results lies in their potential use by DeFi protocol architects and smart contract developers when designing risk management systems, configuring liquidation auction parameters, and selecting the optimal configuration of oracle networks for the Ukrainian crypto market.
O. Kravets, B. Martynenkov, A. Tcvetkov, E. Puzhanova · 7 authors
The article discussed an algorithm for achieving mutual information coordination for a system with distributed ledger technology based on a blockchain. The goal is to develop a generalized approach to formalizing the operation of the distributed ledger technology blockchain system in the course of achieving mutual coordination, including taking into account the possibilities of implementing abnormal functions by the distributed ledger technology blockchain node of the system and grouping nodes. The rules of block chain formation in algorithms for achieving mutual information coordination are proposed. The process of achieving mutual information coordination is described. A mathematical model of the process of achieving mutual information coordination between the nodes of the distributed ledger technology blockchain system is proposed, which differs in the representation of the system by a team of finite automata with the possibility of creating associations (pools) and providing an assessment of the centralization of the system in the conditions of choosing different variants of behaviour strategy by automata.
Open access
Cybersecurity and Information Systems
Advanced Research in Systems and Signal Processing
In modern distributed information systems, the need to ensure a high level of cybersecurity, data integrity, and confidentiality under conditions of interorganizational interaction is steadily increasing.Blockchain technologies enhance transparency and trust among participants; however, traditional consensus mechanisms are accompanied by significant computational overhead, risks of centralization, and limited capabilities for protecting sensitive information.These issues are particularly acute in corporate environments of small and medium-sized enterprises, where the computational resources of network nodes are constrained while the requirements for business data confidentiality remain high.A promising direction is the integration of Zero-Knowledge Proof (ZKP) mechanisms, which enable verification of operation correctness without disclosing the underlying data.Nevertheless, their practical adoption is hindered by the high cost of proof construction for classical cryptographic primitives.In particular, for the SM3 hash function there are no efficient optimized implementations of preimage proofs, and its bit-oriented structure leads to a substantial increase in circuit size and proof generation time, making its use infeasible in resource-constrained environments.This paper proposes a dockerized private blockchain architecture oriented toward corporate environments with limited resources, combining the trust-oriented Proof of Friendship consensus with Zero-Knowledge Proof mechanisms.The key result is the development of an approach for optimizing SM3 hash preimage proofs in ZKP systems.The paper introduces principles of manual optimization of the SM3 circuit representation, including reduction of bitwise operations, aggregation of 1965 constraints, optimization of message expansion, and reduction of round depth.It is shown that these transformations significantly decrease the size of arithmetic circuits and proof generation time compared to naive algorithm translation, enabling practical use of SM3 in zero-knowledge systems and corporate blockchain solutions.The proposed approach provides a balance between blockchain transparency and business data confidentiality, forming a "trust but do not disclose" model.The obtained results establish a scientific and practical foundation for deploying privacypreserving computation in distributed information systems and for developing nextgeneration secure blockchain platforms.
Кваліфікаційна робота бакалавра складається зі вступу, чотирьох розділів, висновків, списку використаних джерел та додатків. Перший розділ кваліфікаційної роботи присвячено дослідженню актуального стану досліджуваної проблематики, обґрунтуванню обраного напряму роботи, а також визначенню та відбору методів і засобів проектування. У другому розділі розглянуто та обґрунтовано підходи й технології для вирішення поставлених завдань. Також наведено функціонально-структурну схему об’єкта проектування та ER-діаграму бази даних. Третій розділ охоплює безпосередню розробку програмного забезпечення та практичне втілення проєктованого об’єкта. Четвертий розділ містить SEO-оптимізацію інформаційно-комп’ютерної системи. У висновках підсумовано результати, отримані в ході виконання всіх попередніх розділів роботи.
The paper investigates the issues of secure functioning of a two-level blockchain with a complex mixed consensus protocol — Proof-of-Work in the main blockchain (mainchain) and Proof-of-Stake in the secondary (sidechain). The principle of building such a blockchain is based on the Proof-of-Proof protocol, where a stable blockchain (mainchain) is used to ensure the stability of the sidechain, by referring the mainchain blocks to the sidechain blocks using special transactions. Such a structure allows for faster block generation in the sidechain and, accordingly, faster processing of transactions without reducing stability and without increasing the block size. In turn, such a two-level blockchain is of the greatest interest for the creation of a cascade system of state registers, which will be guaranteed to be protected against the substitution and forgery of documents. The main results of the work areexplicit analytical expressions for estimates of the probability of double spend attack on such a two-level blockchain, under the condition of an adversary in the sidechain and in the mainchain. The expressions obtained allow finding the number of confirmation blocks in the sidechain, which guarantees security against the attack with a probability no less than a preset value. Keywords: blockchain, mainchain, sidechain, cryptocurrencies, mining, Proof-of-Proof consensus protocol, double spend attack.
This article examines the limitations of existing hybrid rollup solutions and presents an adaptive L2 architecture model that leverages artificial intelligence mechanisms. It is shown that current approaches to combining optimistic and ZK verification are largely based on static rules or manual mode selection, which prevents them from effectively accounting for load dynamics, risk profiles, and domain-specific properties of applications. Based on an analysis of optimistic, ZK, and hybrid rollups, an adaptive hybrid rollup model with AI-based transaction routing is proposed. This model combines transaction classification, GNN-based decision making, LSTM-based network condition forecasting, a dual-path execution system, and a continuous learning module. The article describes a Predictive Routing Algorithm that performs proactive selection between ZK and optimistic paths, taking into account cost, latency, security, and risk profile, as well as a Dynamic Resources Allocation mechanism that dynamically redistributes resources between the paths. The proposed multi-criteria optimization framework demonstrates the ability to tune objective weights to the specifics of different classes of DeFi and Web3 protocols. It is shown that the implementation of such a model is promising for systems with high transactional intensity, as it enables a shift from manual configurations to automated, data-driven policies for resource and risk management in hybrid rollup architectures.
The paper studies DeFi (decentralized finance) as a decentralized system for the circulation of financial tokens in virtual and cryptocurrency spaces. The subject of the study is the basic concepts, structures, and properties of DeFi. The relevance of the work is determined by the presence of unresolved issues related to the conceptual apparatus and structure of DeFi, factors of reduction and methods for determining the level of decentralization of DeFi, the functioning of the DeFi infrastructure, which highlights the need for further research into the concepts, structures and properties of DeFi. The aim of the study is to form a theoretical and methodological foundation for DeFi by clarifying the conceptual apparatus and identifying the features of DeFi functioning. The methodological framework of the study is based on the following principles: an object-subjective approach to describing entities, a method of structural analysis of objects, a systems approach to model objects, a process approach to analyzing the functioning of systems, and a service approach to analyzing interactions between serving and served systems. The study resulted in the formulation of the concept of DeFi (including the concept of a decentralized system). The following were identified: factors of centralization (reduced decentralization) of DeFi; the structure of DeFi as a set of subsystems for the circulation of virtual financial tokens and crypto tokens; a method for assessing the degree of DeFi decentralization as a system for the circulation of digital financial tokens; a three-tier service model of the DeFi infrastructure; and a model for the interaction of financial token circulation processes. Conclusions: The conceptual framework of DeFi, including the definition of DeFi as a decentralized system for the circulation of financial tokens in virtual and crypto spaces, allows us to identify the functional features of DeFi that ensure conditions for significantly greater transparency of the rules and results of financial transactions compared to traditional centralized financial systems. The use of virtual and crypto tokens, along with other DeFi mechanisms in financial circulation, significantly reduces uncertainty and the associated risks of executing financial agreements between economic entities.
Людмила Василівна Ковальчук, Микола Юрійович Кузнєцов, Алла Антонівна Шумська
Розглядається модель функціонування блокчейну, що ґрунтується на протоколі консенсусу Proof-of-Stake, а саме — протоколі Ouroboros Praos. Кожен створений блок стає видимим усім стейкхолдерам з певною затримкою, або часом синхронізації, що є випадковою величиною з натуральними значеннями та заданим дискретним розподілом. Можливе розгалуження блокчейну внаслідок того, що слотлідер може не бачити останній створений блок. Тому в разі утворення нового блока формується посилання на раніше створений видимий блок. Ще однією причиною потенційного розгалуження є наявність декількох слотлідерів у одному й тому самому таймслоті, оскільки у разі застосування протоколу Ouroboros Praos така можливість є. Множина всіх блоків блокчейну, які були будь-коли створені (зважаючи й на ті, що не увійшли до історії блокчейну згідно з правилом «довшої гілки»), утворює дерево, гілками якого є ланцюги блоків, пов’язаних між собою посиланнями. Запропоновано застосовувати алгоритм методу Монте-Карло для оцінки таких характеристик дерева: середня довжина найдовшої гілки, середня ефективність процедури генерації блоків, середня довжина найдовшого розгалуження, а також розподіли відповідних випадкових величин. Числові приклади ілюструють високу точність отриманих оцінок за незначних витрат часу на обчислення.
Possibilities to use distributed ledger technology are shown referring to storing data in information systems of airports and aviation systems of various levels. The features of the operation of a distributed ledger are noted regarding information systems. Various options for generating messages for storage using distributed ledger technology are studied along with the parameters of message flows. The features of using blockchain technology when creating distributed ledger are highlighted in case of the need to correct the stored information. Apossibility to use network technologies is shown for forming distributed ledger, the nodes of which are located at significant distances from each other (registries of several airports). The provided data can be used to create reliable distributed information storage facilities, both within a separate airport and for a group of airports.
Open access
Cybersecurity and Information Systems
Advanced Signal Processing Techniques
Advanced Research in Systems and Signal Processing