Sirvi Autor "Iqbal, Mubashar, juhendaja" järgi

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A Blockchain Solution for Auditing of Timber-to-Charcoal Process
(Tartu Ülikool, 2021) Zubair, Muhammad; Iqbal, Mubashar, juhendaja; Milani, Fredrik Payman, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Arvutiteaduse instituut
Blockchain technology is emerging not only in cryptocurrencies like bitcoin and ethereum but also expanding in other business fields. Due to its diverse nature of architecture, it can easily integrate with such environments, e.g., permissioned or permissionless, state-full or stateless. This article mainly focuses on permissioned blockchain, the hyperledger fabric, how to implement it, and how to use it to automate the audit to the timber-tocharcoal business process. In order to accomplish this study, a design science approach is selected. In this thesis, a timber-to-charcoal case study is analyzed, designed the software architecture, developed the solution using hyperledger fabric, tested and evaluated it with defined evaluation criteria. The technology stack to develop the smart contract and web services to invoke the chaincode and access the ledger is NodeJs. The final evaluation shows that hyperledger fabric is a secure, fast, and decentralized immutable ledger. In conclusion, it is a suitable approach and benefits the audit to timber-to-charcoal business process.
AI-Driven Blockchain-based Federated Learning for Edge Devices
(Tartu Ülikool, 2025) Zhang, Lanxiang; Iqbal, Mubashar, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Arvutiteaduse instituut
The rapid development of the Internet of Vehicles (IoV) has created unprecedented demands for secure, scalable, and privacy-preserving edge computing solutions. While Federated Learning (FL) offers a promising approach to collaboratively train machine learning models across distributed devices without exposing raw data, traditional FL frameworks remain dependent on centralized aggregators, introducing single points of failure, data poisoning attacks, and trust issues in dynamic vehicular environments. To address these challenges, we propose an AI-driven blockchain-based FL framework for IoV that integrates decentralized consensus mechanisms, cryptographic validation, and robust aggregation techniques to enable secure and efficient collaborative learning among untrusted edge devices. The framework leverages a Hyperledger Fabric-based permissioned blockchain network to manage tamper-resistant records of model updates, enforce dynamic reputation systems, and distribute incentives for participation. By combining differential privacy and Byzantine-resilient aggregation, our method significantly reduces the risks of data leakage and model poisoning. Experimental evaluations in a simulated IoV environment demonstrate that the proposed approach achieves comparable accuracy to centralized learning (92.4\% mAP vs. 93.1\% mAP) while reducing attack success rates from 78.5\% to 3.2\% and preserving strong privacy guarantees. This work advances the state of the art in decentralized machine learning and provides a practical foundation for privacy-preserving, trustworthy intelligence in intelligent transportation systems. While existing approaches, such as differential privacy and secure multi-party computation, offer partial protection, they often introduce high computational costs or rely on unrealistic trust assumptions. Blockchain technology, though promising for decentralizing FL workflows, is still challenged by trade-offs between security and scalability—especially in highly mobile, intermittently connected IoV settings.
Blockchain and Digital Twin-based Approach for Securing Water Supply Infrastructure
(Tartu Ülikool, 2024) Tudavekar, Ojus Virendra; Iqbal, Mubashar, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Arvutiteaduse instituut
Digitaalne kaksik (inglise keeles Digital Twins ehk DTs) kui füüsiliste üksuste virtuaalne kujutis annab väärtusliku ülevaate küberfüüsilise süsteemi (CPS) käitumisest ja omadustest. DT võimeid jälgida, visualiseerida, testida ja simuleerida füüsilist protsessi on tööstussüsteemides aastate jooksul laialdaselt kasutatud kvaliteedi ja tõhususe parandamiseks. Lisaks sellele on praegusel kasvava digitaliseerimise ajastul kriitilise tähtsusega vee infrastruktuuri ja küberturvalisuse lähenemine. DT, mida tavaliselt peetakse reaalsete objektide virtuaalsete koopiate loomiseks, omab märkimisväärset potentsiaali veemajanduse CPSi turvalisuse ja vastupidavuse suurendamisel. Plokiahela ja DT-tehnoloogia integreerimine tööstussüsteemide jaoks on hiljuti teadlaste seas populaarsust kogunud. Teadusuuringuid DT kasutamise kohta vee- ja ühissüsteemi turvalisuse suurendamiseks on vähe. Käesolevas töös esitame ulatusliku kirjanduse ülevaate olemasolevast kirjandusest vee CPSi kohta, kus analüüsitakse esmaseid julgeolekuohte, kasutatavaid haavatavusi ja pakutud avastamismehhanisme. Lisaks sellele pakutakse välja uudne lähenemisviis, mille puhul DT on integreeritud plokiahelaga kui rünnaku pettusmehhanismiga, et suurendada veekäitluskeskuste turvalisust, kasutades turvalise veepuhastussüsteemi (SWaT) kui veekäitluskeskuste baasarhitektuuri. Lisaks tutvustatakse ründajate mudeleid, ründestsenaariume ja rollipõhist intsidentidele reageerimise käsiraamatut (IRPs), et ohjeldada ja leevendada rünnakuid Water CPSis. Kavandatud lahendust hinnatakse, kasutades rollipõhist IRP-d erinevate ründestsenaariumide jaoks ja DT-põhist simulatsiooni Microsoft Azure Digital Twin Platform abil.
Blockchain in Edge - Cloud Computing Continuum
(Tartu Ülikool, 2023) Bassey, Iwada Eja; Dehury, Chinmaya Kumar, juhendaja; Iqbal, Mubashar, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Arvutiteaduse instituut
In the era of Edge Computing, Internet of Things(IoT) devices connect and communicate to create a network of objects that can collect information from the environment without human intervention. While the IoT offers many benefits, it also poses several cybersecurity risks, including the lack of detection of malicious IoT sensors, weak authorization, and authentication protocols, and insecure management of data received from IoT devices. Developing new solutions to enhance IoT sensors’ security to address these issues is crucial. One crucial challenge that requires attention is the secure management and storage of data collected from IoT devices at the Edge. Many existing solutions rely on centralized systems vulnerable to tampering and must provide reliable data traceability records. To address this challenge, this thesis proposes a blockchain-based architecture for securing and managing data collected from IoT devices. By leveraging blockchain technology, we create a distributed data storage architecture that eliminates the need for centralized network topologies. This approach offers several advantages, including immutability, decentralization, distributivity, enhanced security, transparency, instant traceability, and increased efficiency through automation. Our results demonstrate that this proposed architecture provides a high level of performance and can be used as a scalable, massive data storage solution for IoT devices using blockchain technologies. One significant advantage of this approach is that new IoT sensors can quickly be enrolled and unenrolled in our architecture without retrofitting. Our system does not depend on any specific communication protocol and can be applied to any IoT application. In summary, our proposed architecture provides a robust and secure solution for managing and storing data collected from IoT devices, thus enhancing the overall security of the IoT devices in the Edge.
Digital Twin and Blockchain-Driven Firmware Updates for the Internet of Vehicles
(Tartu Ülikool, 2024) Miadzieles, Edgar; Iqbal, Mubashar, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Arvutiteaduse instituut
Plokiahel on pälvinud märkimisväärset tähelepanu kui tehnoloogia, mis pakub detsentraliseeritud lahendusi erinevates valdkondades. Plokiahela raamistik pakub autentimist, terviklikkust ja muutumatust tagades usaldust ja turvalisust. Digitaalsete kaksikute hiljutine kasutuselevõtt on võimaldanud simuleerida ja testida virtuaalses keskkonnas, peegeldades füüsilisi üksusi, nende keskkonda ja protsesse. Selle lõputöö eesmärk on uurida püsivara uuendamise protsessi kasutades kaablita sidevahendeid intelligentse transpordisüsteemi ja täpsemalt sõidukite interneti kontekstis. Praegused kaablita sidevahenditega tarkvara värskendused sõltuvad klient-serveri mudelist, samas kui sõidukite internet ja intelligentne transpordisüsteem saavad kasu detsentraliseeritud lahendusest, mis eemaldab nõrgima lüli tõrke erinevate rünnakute ning võrgu ummistuse mured. Kasutame plokiahela ja digitaalse kaksiku tehnoloogiaid, et täita sõidukite interneti ja intelligentse transpordisüsteemi kriteeriume, võimaldamaks kaablita sidevahenditega püsivara värskendamise protsessi sõidukite interneti keskkonnas olevate sõidukite jaoks. See lõputöö esitab süstemaatilise ülevaate olemasolevast kaablita sidevahenditega püsivara värskenduste kirjandusest, mis kasutab plokiahela ja digitaalse kaksiku tehnoloogiat. Lisaks pakutakse välja lahendus kaablita sidevahendiga püsivara värskenduste jaoks, mis on realiseeritud Ethereumi ja Microsoft Azure Digital Twins technoloogia abil, et rahuldada sõidukite interneti keskkonnas olevate sõidukite turvalise püsivara värskenduste nõudeid. Pakutava lahenduse nutilepingut hinnatakse gaasitarbimise ja ühikutestide põhjal. Kavandatav lahendus töötatakse välja konsoolirakendustena mida hinnatakse kirjanduse süstemaatilise ülevaate ning sõidukite interneti ja intelligentse transpordisüsteemi kontekstuaalsest analüüsist tuletatud disainikriteeriumide alusel.
Digital Twin-Based Deception Solution for Autonomous Vehicles Security
(Tartu Ülikool, 2025) Khan, Md Al Amin; Muhammad, Naveed, juhendaja; Iqbal, Mubashar, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Arvutiteaduse instituut
The autonomous vehicle industry is rapidly advancing toward fully autonomous vehicles, raising significant concerns about cybersecurity and physical safety. These vehicles depend heavily on interconnected digital components, which enhance convenience, but at the same time pose risks. Those interconnected components expose critical systems to malicious actors. Recent incidents have demonstrated that adversaries are employing sophisticated techniques to exploit these systems, posing a greater risk to human life, data security, and public safety. This reminds us that the security of autonomous vehicles needs to be addressed. This study addresses the problem of securing autonomous vehicles against cyber threats by employing a digital twin-based deception solution. Here we show that our proposed digital twin deception system can effectively mitigate unauthorized access attempts targeting autonomous vehicles, redirecting them to an isolated honeypot and collecting valuable intelligence while keeping the attacker busy on the honeypot. At the same time, the data is visualised on the Kibana dashboard. This method not only identifies intrusions but also generates actionable insights through integrated monitoring and incident response features. The proposed system can also be extended beyond autonomous vehicles; it can also be applied to other cyber-physical models where a digital twin offers significant security and operational advantages. These findings contribute to the larger effort of protecting next-generation transportation systems through intelligent, resilient, and adaptive security mechanisms.
Harnessing Blockchain and Digital Twin for Security Risk Assessment in Internet of Vehicles
(Tartu Ülikool, 2023) Ahmed, Ashfaq Hussain; Iqbal, Mubashar, juhendaja; Suhail, Sabah, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Arvutiteaduse instituut
Digitaalne kaksik (inglise keeles Digital Twins ehk DTs) on virtuaalne representatsioon füüsilistest objektidest, mida kasutatakse katsetamiseks, simulatsiooniks ja prototüüpimiseks enne vastava füüsilise komponendi valmistamist. Digitaalse kaksiku tehnoloogiat on laialdaselt kasutatud nutika tootmise valdkonnas mitu aastat, et täiustada kõiki selle tegevusvaldkondi. Veelgi enam, viimase kümnendi jooksul on plokiahela tehnoloogia ja digitaalsed kaksikud tööstussüsteemides muutunud teadlaste seas üha populaarsemaks. Tänu hiljutistele edusammudele targa linna ja intelligentse transpordisüsteemi (ITS) valdkonnas on sõidukite interneti (IoV) kontseptsioon muutumas üha levinumaks. Digitaalne kaksik ehk virtuaalne koopia füüsilisest maailmast pakub tohutut potentsiaali selleks, et tõsta tarkade linnade kõigis osades turvalisust ja vastupidavust, hõlmates seejuures sõidukite interneti turvalisust ja vastupidavust, enne selle kasutuselevõttu reaalses maailmas. Plokiahela tehnoloogial põhinevate digitaalsete kaksikute kasutamist sõidukite interneti turvalisuse suurendamisel on seni vähe uuritud. Käesolevas magistritöös esitatakse põhjalik süstemaatiline ülevaade olemasolevast kirjandusest, kus plokiahelal põhinevaid digitaalseid kaksikuid on soovitatud kasutada tööstussüsteemide täiendavateks turvakihtideks. Lisaks pakutakse sõidukite interneti turvaohtude käsitlemiseks välja uudne plokiahelal põhinev turberaamistik. Samuti tutvustatakse sõidukite interneti turvaohtude modelleerimist ja riskijuhtimist ning selgitatakse, kuidas pakutud plokiahelapõhine raamistik maandab sõidukite interneti riske. Riskide maandamiseks pakutud lahendust hinnatakse V2S-side (Vehicle-to-Sensor) jaoks digitaalsel kaksikul põhineva simulatsiooni abil. Kasutusjuhtumi simuleerimiseks kasutati selles magistritöös Microsoft Azure Digital Twin platvormi.
Model-Driven Engineering of Blockchain Oracles
(Tartu Ülikool, 2022) Levasseur, Olivier; Iqbal, Mubashar, juhendaja; Matulevicius, Raimundas, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Arvutiteaduse instituut
Blockchain is a decentralized ledger technology that provides data storage with strong integrity properties without the need for a trusted authority. Model-driven engineering is a software engineering discipline that aims at working with domain models instead of source code. Blockchain oracles are software components that can provide a communication channel between traditional off-chain applications and smart contracts. Model-driven engineering solutions have started being used to facilitate the development of blockchainbased applications through domain models. However, our literature review shows that there are limitations in the identified solutions to model blockchain oracles and that some types of oracles cannot be modeled through these solutions. In this thesis, we define a meta-model to illustrate the main concepts of the blockchain oracle domain and the relationships between them. We define a UML profile that extends the UML sequence diagram to include elements to model blockchain oracles. Our model also includes security components to provide encrypted communication with the oracles. A MagicDraw plugin is developed to implement transformation rules that automatically translate an oracle model into a standalone application. This results in a model-driven engineering solution that facilitates the modeling of secure blockchain oracles. The contribution of this thesis is evaluated based on functional and security requirements using an evaluation scenario that involves four different types of oracles interacting with an off-chain application.
OwlParser: Parsing OWL-based Blockchain Security Ontology
(Tartu Ülikool, 2022) Ristioja, Mai; Iqbal, Mubashar, juhendaja; Matulevicius, Raimundas, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Arvutiteaduse instituut
Ontology representations are often used in areas when the knowledge is still incoherent and there exists a need to clarify and agree on definitions, concepts and relations. Ontology representations in their written form are however difficult to comprehend and thus tools for better exploring and understanding the information contained therein are in demand. Some tools providing such functionality exist, of which Protégé is the most common. This, however, is a professional-use application which can be difficult to use for less experienced user and which also needs installation. The aim for this thesis is to develop a web-based tool for exploring ontology representations based on the security and risk management (SRM) domain model and which also provides additional features to support ontology representations about blockchain security. The developed tool named OwlParser loads OWL files from the local computer or the web, allows browsing the content of the ontology representation and provides SRM-based navigation. We hope the tool will be useful for both students as well as professionals in helping to study and explore SRM-based ontology representations.
Plokiahelal põhinevate digitaalsete kaksikute kasutamine tervishoius
(Tartu Ülikool, 2025) Zhang, Xinjian; Iqbal, Mubashar, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Arvutiteaduse instituut
The healthcare industry faces increasing challenges like rising costs, fragmented data, and a growing demand for personalized care. Digital Twin (DT) technology offers a promising response by enabling real-time monitoring and predictive analytics through virtual replicas of physical entities. However, its adoption in healthcare remains limited due to concerns about data security, interoperability, and system scalability. This study proposes a blockchain-enabled DT framework designed specifically for healthcare applications. The framework integrates secure data sharing, traceability, and tamper resistance through blockchain technology. Developed using the Design Science Research (DSR) methodology, the framework design is informed by a Systematic Literature Review (SLR) that identifies core DT components and implementation challenges in healthcare contexts. A prototype was implemented using a smart patient room scenario to demonstrate feasibility. The system combines IoT sensors, Azure Digital Twins (ADT), and Ethereum-based blockchain logging to support real-time monitoring and secure data handling. Evaluation through stakeholder interviews revealed that the system was perceived as intuitive, technically sound, and clinically relevant, though limited in functionality due to its prototype nature. The results of this work demonstrate how DT and blockchain technology can be integrated into a cohesive framework that supports secure, responsive, and modular digital healthcare systems. Additionally, this work offers both practical insights and theoretical contributions toward advancing the role of emerging technologies in modern healthcare systems.
Scalability Assessment in Blockchain-enabled IoT Applications
(Tartu Ülikool, 2023) Sipilä, Heikki Santeri; Iqbal, Mubashar, juhendaja; Affia, Abasi-amefon Obot, juhendaja; Lai, Russell W. F., juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Arvutiteaduse instituut
Plokiahela kasutamine Asjade Internetis (IoT) on loonud tee detsentraliseeritud IoT-rakenduste loomisele. Plokiahela integreerimine IoT-ga ei ole aga lihtne ja pakub erinevaid väljakutseid. Tegime nende võimalike väljakutsete uurimiseks läbi süstemaatilise kirjanduse ülevaate (SLR). SLR tulemuseks oli kaks järeldust. Esimene järeldus oli, et plokiahela toega IoT-rakenduste võimalikud mastaapsuse probleemid hõlmavad salvestus-, võrgu-, töötlemis- ja läbilaskevõimega seotud väljakutseid. Teine järeldus oli, et praeguses kirjanduses puuduvad vahendid ja meetodid nende mastaapsuse väljakutsete hindamiseks. Me tegeleme selle uurimislüngaga, pakkudes esmalt meetodi mastaapsuse hindamise tööriista loomiseks plokiahela toega IoT-rakenduste jaoks. Seejärel tutvustatakse seda meetodit selles lõputöös, kavandades, juurutades ja valideerides tööriista, mida saab kasutada nende rakenduste skaleeritavuse hindamiseks. Meie pakutud tööriist kasutab olemasolevat virtualiseerimistarkvara, et luua simuleeritud IoTseadmeid, mis võimaldab testida nende rakenduste mastaapsust ilma füüsilisi seadmeid kasutamata. Valideerisime tööriista skaleeritavuse testimisega selle lõputöö osana välja töötatud kontseptsiooni tõestusega plokiahela toega IoV-rakendusega. Seejärel analüüsiti nende testide tulemusi ja hinnati tööriista teostatavust sobivaks skaleeritavuse testimiseks maksimaalselt 24 seadmega.
Secure Data Sharing in the Internet of Vehicles Using Blockchain-based Federated Learning
(Tartu Ülikool, 2025) Luzan, Mykyta; Iqbal, Mubashar, juhendaja; Matulevičius, Raimundas, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Arvutiteaduse instituut
The Internet of Vehicles enables connected vehicles to share data and collaboratively learn to enhance road safety and traffic efficiency. Federated learning has emerged as a promising approach for enabling privacy-preserving collaborative learning among vehicles, allowing them to jointly train machine learning models without sharing raw sensitive data. However, the centralized architecture commonly used in federated learning introduces significant security vulnerabilities that can compromise system integrity and reliability. While extensive research exists on federated learning security in general, there is insufficient analysis of how these security challenges manifest in specific application contexts, particularly in dynamic environments like IoV. Here we show that integrating Hyperledger Fabric’s permissioned blockchain with zero-knowledge proofs creates a comprehensive security framework that effectively protects federated learning systems against both model tampering, aggregation protocol violation, and unauthorized access while maintaining privacy. Our systematic analysis and implementation reveals that blockchain technology can address core vulnerabilities in centralized federated learning architectures while preserving their privacy benefits, demonstrating advantages over previous approaches that relied solely on cryptographic protocols or trusted third parties. By validating our framework through a concrete IoV data sharing implementation, we establish a practical foundation for securing federated learning in distributed environments. The implications of this research extend beyond vehicular networks to any domain requiring secure collaborative learning among distributed participants. As autonomous systems become increasingly interconnected, this work demonstrates how combining blockchain with federated learning can enable trustworthy data sharing while preserving both privacy and security.
Securing the Bridges Between Two Worlds: A Systematic Literature Review of Blockchain Oracles Security
(Tartu Ülikool, 2023) Chiarelli, Alessandro; Iqbal, Mubashar, juhendaja; Fagerholm, Fabian, juhendaja; Matulevičius, Raimundas, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Arvutiteaduse instituut
Blockchain technology has paved the way for the decentralization of Internet services. It achieves this using a decentralized and distributed ledger that can withstand single points of failure. The ledger is secured through advanced cryptographic techniques and a decentralized consensus mechanism that ensures its resistance to tampering. Blockchain is a self-enclosed system, usually called on-chain world. To interact with the rest of the internet outside the blockchain (e.g., off-chain world), we need to set up interfaces to let the two worlds interact. These interfaces are called oracles. Given the role of the oracles in a blockchain system, it is paramount to design and implement them securely. We perform a systematic literature review that shows not much research is done into studying the security aspects of blockchain oracles. The research mostly focuses on the economic aspects of the oracles or on how to implement or design oracles that can benefit some specific use cases. In this thesis, we select two inbound oracles and implement them to evaluate and compare them from a security point of view. The contribution of this thesis consists of a literature review motivating the need for further research on the topic and comparing two inbound oracles, as the technique used to perform them can be extended and adjusted to other oracles as well. We also present the implementation of an outbound oracle for completeness and discuss its security properties. Furthermore, we present a novel approach that makes use of a decentralized oracle network (i.e., Chainlink) to build a system that fetches off-chain data to the blockchain and then securely retakes the data off-chain, such that there is no need to trust the oracle nodes. The technique we propose is thus blockchain and oracle agnostic and can be applied in various situations.
Towards Developing a Blockchain Selection Toolkit for Smart Cities
(Tartu Ülikool, 2025) Zhang, Xinyue; Iqbal, Mubashar, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Arvutiteaduse instituut
In recent years, the rapid development of smart cities has driven the integration with innovative technologies such as blockchain to enhance urban systems' efficiency, transparency, and credibility. This thesis presents a comprehensive and systematic survey of blockchain applications in smart cities and proposes a toolkit of blockchain options for the diverse needs of smart cities. The study firstly reviews the background of blockchain technology and smart city framework, followed by a systematic literature review of public, private, and federated chains, and analyzes the challenges faced during their integration. Based on this, a blockchain selection toolkit is designed and implemented to provide city planners with references on selecting appropriate blockchain technologies in different smart city scenarios through existing cases. The toolkit is evaluated through three case studies: a small-scale energy grid, a large-scale supply chain system, and a secure healthcare system. Finally, the thesis discusses the practical implications of the research, answers the research questions, and identifies the limitations and future directions of the research. The study results show that the proposed toolkit supports adoption decisions for smart city blockchain technology.