The growing reliance on digital services has led to an escalation in cyber risks and attacks targeting banks and financial institutions. Such cyber threats necessitate innovative solutions. But to achieve it, one needs to overcome the challenges of seeking reliable information on utilizing blockchain technology to combat cyber-attacks. Hence, this work aims to use a systematic literature review to study the potential of blockchain technology to mitigate cyber threats in the banking and financial sector as well as the advantages and challenges of blockchain technology. Blockchain provides heightened security, improv transaction processes, ensures transparency and privacy, optimizes operational performance, and reduces fraud. Despite its advantages, challenges like regulatory compliance, privacy concerns, and scalability need careful consideration. Prominent institutions like Bank of America, HSBC, and J.P. Morgan are actively investigating blockchain integration. To ensure wise choices regarding blockchain use in organizations with valuable data and assets, advisors and business leaders must fully grasp both the advantages and possible drawbacks of this technology. Armed with this information, financial institutions gain essential insights, steering them towards judicious choices concerning the integration and utilization of blockchain technology, thereby enhancing, and reinforcing their cybersecurity framework. / Den ökande användningen av digitala tjänster har resulterat i en ökning av cyberrisker och attacker riktade mot banker och finansinstitutioner. Cyberhot fortsätter att utmana säkerheten för finansiella institutioner, vilket kräver nyskapande lösningar. För att uppnå det måste man övervinna utmaningarna med att söka tillförlitlig information angående användningen av blockkedja teknik för att bekämpa cyberattacker. Därför syftar detta verk till att använda systematisk litteraturgenomgång för att utforska potentialen hos blockkedjeteknik för att mildra cyberhot inom bank- och finanssektorn, samt för- och nackdelar med teknologin. Blockkedja teknik erbjuder förhöjd säkerhet, optimerar transaktionsprocessen, säkerställer transparens och integritet, ökar operativ prestanda och minskar risken för bedrägeri. Trots dessa fördelar måste utmaningar som regeluppfyllelse, integritetsfrågor och skalbarhet hanteras med omsorg. Framstående institutioner som Bank of America, HSBC och J.P. Morgan undersöker aktivt integration av blockkedja teknik. För att säkerställa kloka beslut kring blockkedjeanvändning i organisationer med viktig information och tillgångar är det avgörande att rådgivare och företagsledare har en djup förståelse för både fördelar och möjliga nackdelar med teknologin. Med denna insikt i ryggen får finansinstitutioner värdefull vägledning när det gäller integration och användning av blockkedjeteknik, vilket stärker och förbättrar deras ramverk för cybersäkerhet.

[pt] A redução da poluição e das emissões de gases de efeito estufa tem sido o foco de um grande esforço global. Nesse contexto, Certificados de Energia Renovável (RECs) são de grande importância para incentivar mudanças na matriz energética, visando à adoção de práticas sustentáveis. Dado o crescimento deste mercado e as características dos RECs, uma das potenciais ferramentas impulsionadoras da sua adoção é o protocolo de rede blockchain. Nesta pesquisa, analisamos três modelos autônomos de emissão e venda na blockchain de tokens baseados em RECs em condições de incerteza para um gerador de energia renovável. Nos três modelos, o gerador tem a opção de investir agora ou daqui a um ano para ter o direito de emitir RECs e ofertá-los através de leilões de venda trimestrais. No primeiro, assumimos que o preço do token é fixo, seguindo o conceito de uma stable coin. No segundo, consideramos que o preço segue uma função inversa da demanda sujeita a choques estocásticos. Finalmente, no terceiro, a demanda por RECs é incerta e busca-se maximizar o lucro do gerador. Realizamos uma aplicação numérica para verificarmos a validade dos modelos e concluímos, considerando os parâmetros adotados, que o gerador deverá investir no segundo modelo, pois foi o que apresentou maior VPL ( 60.992,70 Reais). Contudo, se a volatilidade da demanda for inferior a 20,00 por cento, o modelo ótimo para o gerador é o primeiro modelo. A principal contribuição deste trabalho é analisar a dinâmica do desempenho de produtos digitais sob incerteza. / [en] Reducing pollution and greenhouse gas emissions has been the focus of a major global effort. In this context, Renewable Energy Certificates (RECs) are important as they provide incentives for changes in the energy matrix, towards the adoption of sustainable practices. Given the growth of this market and the characteristics of RECs, one of the potential drivers of their adoption is the blockchain network protocol. In this research, we analyze three autonomous models for issuing and selling in the blockchain of REC based tokens for the renewable energy generator. In all three models, the generator has the option to invest now or in one year for the right to issue RECs and offer them through quarterly sales auctions. In the first model, we assume that the token price is fixed following a stable coin concept. In the second model, we consider that the price follows an inverse demand function subject to stochastic shocks. Finally, in the third model, the demand for RECs is uncertain and the purpose is to maximize the generator s profit. Through a numerical application, we verify the validity of the models and conclude, considering the parameters adopted, that the generator should invest in the second model, since it was the one with the highest NPV (60,992.70 real). However, if the demand volatility is less than 20.00 percent, the optimal model for the generator is the first model. The main contribution of this work is to analyze the performance dynamics of digital products under uncertainty.

[pt] Este trabalho apresenta uma proposta de implementação de uma blockchain privada gerenciada por agentes de software para armazenar dados de sáude. A tecnologia blockchain está mudando a maneira com que dados privados são armazenados. Agora é possível compartilhar informações sem revelar quem é o dono da informação. Este trabalho apresenta um sistema que permite que usuários armazenagem dados de saúde em uma blockchain gerenciada por agentes de software. Pesquisas revelaram que dados de saúde devem ser armazenado em blockchains privadas, pois são privadas e não devem ser acessíveis para qualquer pessoa como em blockchains públicas. Técnicas de engenharia de software foram utilizadas para desenvolver a arquitetura proposta. O resultado é uma blockchain privada capaz de manipular dados no padrão HL7 e armazena-los de forma anônima e privada. Agentes de software foram utilizados para realizar todo o processo de recebimento, validação e inserção de dados no blockchain. / [en] This paper presents an implementation approach for a private blockchain that is managed by software agents for healthcare data storage. Blockchain technology is changing the way we store private information. Now, it is possible to share private information while not revealing its owner s identity. This paper presents a solution, which enables users to store medical data by using blockchains along with software agents. Further research work has shown that healthcare data, as sensitive information, should be stored in private blockchains through the use of appropriate methods. Software engineering techniques have been used to achieve the proposed solution. The result is a private blockchain that is suitable for manipulating HL7 data, ensuring anonymity and privacy. This can be achieved through software agents that act as regulatory controls for the private blockchains.

[pt] Blockchain e Tangle são estruturas de dados usadas para criar um registro público imutável de dados segurados por uma rede de participantes peer-to-peer que mantém um conjunto de registros de dados em constante crescimento conhecidos como ledgers. As tecnologias Blockchain e Tangle são uma solução descentralizada que garante a troca de grandes quantidades de mensagens confiáveis, entre bilhões de dispositivos de IoT conectados, os quais são muito valiosos, desde que sejam válidos e completos. Esse mecanismo de mensagens peer-to-peer altamente criptografado e seguro é adotado neste projeto para gerenciar o processamento de transações de IoT e a coordenação entre os dispositivos que interagem com o processo. Para manter as transações privadas e seguras, os algoritmos de consenso distribuídos são responsáveis por validar e escolher as transações e registrá-las no ledger global. Os resultados mostraram que a velocidade dos algoritmos de consenso pode afetar a criação em tempo real de histórias confiáveis que rastreiam os eventos das redes IoT. Após incorporar o Processamento de Eventos Complexos, que permite selecionar apenas os eventos de alto nível, é possível obter uma melhoria em muitas situações. O resultado é um sistema Middleware que fornece framework para a construção de aplicativos de larga escala onde podem usar Processamento de Eventos Complexos e diferentes ledgers descentralizados, como o blockchain da Ethereum ou IOTA Tangle, para armazenamento seguro de dados. / [en] Blockchain and Tangle are data structures and protocols used to create an immutable public record of data ensured by a network of peer-to-peer participants that maintain a monotonic constantly growing set of data records known as ledgers. Both technologies provide a decentralized solution that guarantees the exchange, among billions of IoT devices, of large amounts of trusted messages, which are very valuable as long as they are valid and complete. This highly encrypted and secure peer-to-peer messaging mechanism is adopted in this project to manage the processing of IoT transactions. To maintain transactions private, and secured consensus algorithms are responsible for validating and choosing transactions and recording them in the global ledger. The results showed that the speed of the consensus algorithms can affect the creation in real-time of reliable stories that track the events of the IoT networks. After incorporating Complex Event Processing that allows selecting only those high-level events, it is possible to obtain an improvement in many situations. The result is a Middleware system that provides a framework for the construction of large-scale computer applications that use Complex Events Processing and different decentralized ledgers such as the blockchain of Ethereum or IOTA Tangle, for secure data storage.

<p>In service-oriented architecture, services can communicate and share data among themselves. This thesis presents a solution that allows detecting several types of data leakages made by authorized insiders to unauthorized services. My solution provides role-based and attribute-based access control for data so that each service can access only those data subsets for which the service is authorized, considering a context and service’s attributes such as security level of the web browser and trust level of service. My approach provides data protection in transit and at rest for both centralized and peer-to-peer service architectures. The methodology ensures confidentiality and integrity of data, including data stored in untrusted cloud. In addition to protecting data against malicious or curious cloud or database administrators, the capability of running a search through encrypted data, using SQL queries, and building analytics over encrypted data is supported. My solution is implemented in the “WAXEDPRUNE” (Web-based Access to Encrypted Data Processing in Untrusted Environments) project, funded by Northrop Grumman Cybersecurity Research Consortium. WAXEDPRUNE methodology is illustrated in this thesis for two use cases, including a Hospital Information System with secure storage and exchange of Electronic Health Records and a Vehicle-to-Everything communication system with secure exchange of vehicle’s and drivers’ data, as well as data on road events and road hazards. </p><p>To help with investigating data leakage incidents in service-oriented architecture, integrity of provenance data needs to be guaranteed. For that purpose, I integrate WAXEDPRUNE with IBM Hyperledger Fabric blockchain network, so that every data access, transfer or update is recorded in a public blockchain ledger, is non-repudiatable and can be verified at any time in the future. The work on this project, called “Blockhub,” is in progress.</p>

The Swedish central bank has in 2018 launched an investigation into what a digital e-currency in Sweden would look like. Tendermint is being investigated for a potential implementation. Tendermint is a blockchain building environment which has its own consensus-algorithm, and its own solution to the Byzantine general's problem. The most relevant part is the scalability and reliability of Tendermint. To do this we tested out the software by sending transactions between our computers, and recorded its performance in the case of one node and two nodes. After a series of simulations, we then come to the conclusion that indeed Tendermint is a suitable software for a potential e-krona.

The monetary policies of states and systems built upon them do not naturally allow transactions of a very small value, as the transaction costs exceeds the actual value of the transaction. These types of transactions are called micropayments. This is problematic as it removes the possibility to monetize content that has a valuation that is so low that the costs of the transaction exceeds the value of the content. In this thesis we aim to create a system that allows micropayments to monetize low value content. We do so by developing a design theory based on Gregor and Jones conceptual model for design theories within Information Systems research. The system that we develop will use the end users computational power to generate a value, by running a cryptocurrency miner. We present the background knowledge required to fully understand the presented design theory. Within the design theory, we present a theoretical framework to base systems on that enables micropayments through cryptocurrency mining. We also present a developed proof of work prototype that proves the validity of the theoretical framework. Lastly we discuss our design theory. We conclude that the design theory enables transactions of a very low value, such as 0,0001 \$ cents. Transactions of such small value is not possible with systems built upon states monetary policies. We also conclude that the proposed design theory can be further developed to function independently of cryptocurrency mining. Instead the value for the transaction could be generated through solving complicated problems if institutions are willing to pay for computational power to solve them.

Crowdfunding challenges century long boundaries between the public, the industry andinnovation. In that respect the phenomenon holds the potential to decentralize and democratizethe way ventures are financed and realized. Crowdfunding has seen a lot of exitingdevelopments during the last few years, partly because of new crowdfunding platformsemerging on the internet, and partly because of new ground-breaking technology being used forfunding purposes. Meanwhile research has not quite catched up with the recent developments ofdifferent models for crowdfunding. This study’s aim is therefor to give an comprehensiveoverview of the different models of crowdfunding that are being utilized by crowdfundingplatforms on the internet today. A deductive content analysis has been made of 67 currentcrowdfunding platforms. The platforms have been analysed in order to determine what model ofcrowdfunding they utilize. The result has, apart from partly confirming prior studies, alsoproduced new exiting findings on what mechanisms constitute some of the crowdfundingmodels we see today. A new taxonomy of crowdfunding models is discussed and proposed. Theconclusion is that the need for a updated taxonomy, like the one this study provides, was wellneeded in order to understand the field. One important finding is that blockchain technology hasproduced a new form of crowdfunding through cryptocurrency: Initial coin offering. Thatparticular area will likely develop and continue to decentralize and democratise the economicalhuman interaction when it comes to financing.

Globalization and the surge of competition across industries forced companies to improve their supply chain capabilities to serve their customers efficiently and effectively. Due to this fact, businesses are no longer capable of handling all supply chain operations without collaboration and coordination with other firms. One of the key obstacles to coordination is the lack of information sharing and trust between firms since they view information as a sensitive asset. Digital technologies like blockchain, with its inherited features, have the capability to facilitate real-time information sharing, solve trust issues, and improve end-to-end visibility across the supply chain. This licentiate thesis highlights the impact of multiple aspects of information sharing on the bullwhip effect mitigation and explores the potential of blockchain technology as a new coordination mechanism for reducing information distortions, enhancing trust, and orchestrating decision making. Three research papers have been produced within this context and are appended to the thesis. Paper A presents an information sharing-based blockchain architecture to mitigate the bullwhip effect in service supply chains. Paper B aims to explores the literature in terms of using multiple aspects of information sharing to lessen the bullwhip effect. Finally, Paper C introduces an agent-based modeling and simulation approach for two aspects of information sharing: “what to share” and “how to share.” The results show that blockchain technology does provide a significant solution to trust-based issues and information sharing visibility considering the bullwhip effect mitigation. The results also provide a guide for supply chain managers to achieve better coordination and serve as a roadmap for supply chain researchers.

The adoption of blockchain technology for cross-border payments is not an easy task.However this qualitative study further investigates the connotations associated with adoptionof blockchain in cross-border financial transactions within Swedish financial institutions suchas banks, fintech, and credit management service companies. To answer this question, weinterviewed six participants that work in a credit management company, an open bankingcompany, and a digital mortgage service company using semi-structured interviews. Datacollection was done using this method because the purpose of this research work is to identifypeople's insights and experiences based on their real-life experiences. Data were analyzedusing thematic analysis. Our results showed that the impact of adoption of blockchain incross-border payment transactions in terms of technical implementation challenges,customers' use cases and pilot programs, compliance and security enhancements, industrycollaboration and knowledge sharing, legacy systems integration and interoperability, and keydrivers beyond adoption. In addition, the study findings were compared with the determinantsand influence factors of the model through the lens of the DOI. The implications of this studycould used to help financial institutions' focus on blockchain adoption in cross-borderpayment transactions. As a whole, this study contributes to the idea that financial institutionsshould develop an accurate strategy, as well as guidelines that can assist them in leveragingblockchain technology for cross-border payments, enhancing their services, and fosteringsustainable growth in cross-border digital markets.