Blockchain Papers

Leonardo Dias Menezes, Luciano Vieira de Araújo, Marislei Nishijima

No abstract is available for this record.

Pablo Santamaría, Llanos Tobarra, Rafael Vargas, Antonio Robles-Gómez

The digital revolution is renewing many aspects of our lives, which is also a challenge in judicial processes, such as the Chain-of-Custody (CoC) process of any electronic evidence. A CoC management system must be designed to guarantee them to maintain its integrity in court. This issue is essential for digital evidence’s admissibility and probative value. This work has built and validated a real prototype to manage the CoC process of any digital evidence. Our technological solution follows a process model that separates the evidence registry and any evidence itself for scalability purposes. It includes the development of an open-source smart contract under Quorum, a version of Ethereum oriented to private business environments. The significant findings of our analysis have been: (1) Blockchain networks can become a solution, where integrity, privacy and traceability must be guaranteed between untrustworthy parties; and (2) the necessity of promoting the standardization of CoC smart contracts with a secure, simple process logic. Consequently, these contracts should be deployed in consortium environments, where reliable, independent third parties validate the transactions without having to know their content.

Brian Michael Murphy, Asad J. Malik

This interview, which took place in September 2021, explores the history of projects carried out by Jadu and the possibilities of Web3, NFTs, and the futures of data in the metaverse.

Fernando Richter Vidal, Naghmeh Ivaki, Nuno Laranjeiro

No abstract is available for this record.

Tang Gui, Wuzheng Tan, Mei Cai

In the big data era, machine learning has devel-oped prominently and is widely used in real-world systems. Yet, machine learning raises fairness concerns, which incurs discrimination against groups determined by sensitive attributes such as gender and race. Many researchers have focused on developing fairness audit technique of machine learning model that enable users to protect themselves from discrimination. Existing solutions, however, rely on additional external trust as-sumptions, either on third-party entities or external components, that significantly lower the security. In this study, we propose a trustless verifiable fairness audit framework that assesses the fairness of ML algorithms while addressing potential security issues such as data privacy, model secrecy, and trustworthiness. With succinctness and non-interactive of zero knowledge proof, our framework not only guarantees audit integrity, but also clearly enhance security, enabling fair ML models to be publicly auditable and any client to verify audit results without extra trust assumption. Our evaluation on various machine learning models and real-world datasets shows that our framework achieves practical performance.

Eliza Mik

No abstract is available for this record.

Chuan Chen, Yuecheng Li, Zhenpeng Wu, Chengyuan Mai · 8 authors

Metaverse, the core of the next-generation Internet, is a computer-generated holographic digital environment that simultaneously combines spatio-temporal, immersive, real-time, sustainable, interoperable, and data-sensitive characteristics. It cleverly blends the virtual and real worlds, allowing users to create, communicate, and transact in virtual form. With the rapid development of emerging technologies including augmented reality, virtual reality and blockchain, the metaverse system is becoming more and more sophisticated and widely used in various fields such as social, tourism, industry and economy. However, the high level of interaction with the real world also means a huge risk of privacy leakage both for individuals and enterprises, which has hindered the wide deployment of metaverse. Then, it is inevitable to apply privacy computing techniques in the framework of metaverse, which is a current research hotspot. In this paper, we conduct comprehensive research on the necessity, taxonomy and challenges when privacy computing meets metaverse. Specifically, we first introduce the underlying technologies and various applications of metaverse, on which we analyze the challenges of data usage in metaverse, especially data privacy. Next, we review and summarize state-of-the-art solutions based on federated learning, differential privacy, homomorphic encryption, and zero-knowledge proofs for different privacy problems in metaverse. Finally, we show the current security and privacy challenges in the development of metaverse and provide open directions for building a well-established privacy-preserving metaverse system. For easy access and reference, we integrate the related publications and their codes into a GitHub repository: https://github.com/6lyc/Awesome-Privacy-Computing-in-Metaverse.git.

Vasilis Kostakis, Alex Pazaitis, Minas Liarokapis

Technological imaginaries have been increasingly shaping the future perceptions of cities. From artificial intelligence and distributed ledger technology to three-dimensional printing, high-tech artifacts are very often the premises of such imaginaries. However, technology does not only refer to artifacts. Technology also encompasses the processes around the artifacts: how the artifacts are designed, manufactured, used, maintained, and disposed. From this perspective, high-tech visions often disregard problems that pertain to resource extraction, labor exploitation, energy use, and material flows. On the contrary, low-tech and localized alternatives incite lower impact and higher resilience visions. However, they fail to offer solutions of the desired scale and intensity. To address this tension, we provide an alternative vision for mid-tech: a balance between the opposite extreme qualities of low-tech and high-tech. Through a case of open-source prosthetics, we illustrate how to synergistically combine the efficiency and versatility of high-tech solutions with the potential for autonomy and resilience that low-tech offers. Then we discuss a mid-tech approach for distributed ledger technology from a city as a license lens. We provide connections with existing or conceptual applications to show how distributed ledger technology could support more socially and ecologically responsible data practices for city governance.

Marco Ortu, Giacomo Ibba, Claudio Conversano, Roberto Tonelli · 5 authors

No abstract is available for this record.

Zeli Wang, Weiqi Dai, Ming Li, Kim‐Kwang Raymond Choo · 5 authors

No abstract is available for this record.

Leon Yehuda Anidjar, Nizan Geslevich Packin, Argyri Panezi

No abstract is available for this record.

Md. Nizamuddin, Krishna Devarapu, Abhishake Reddy Onteddu, RamMohan Reddy Kundavaram

This paper examines how encryption and AI protect financial blockchain transactions. As blockchain technology grows more important in decentralized finance, AI must be included to solve cybersecurity issues. The research focuses on how AI improves cryptography systems, blockchain-based financial operations, and transaction security. Secondary data from the literature, peer-reviewed publications, and case studies are analyzed to synthesize AI-blockchain cryptography expertise. AI provides real-time anomaly identification, fraud prevention, predictive analytics, consensus mechanism optimization, and key management improvements, boosting blockchain security. Traditional cryptography methods become more adaptable and robust to emerging threats using AI. According to the research, the computational complexity of AI-driven solutions and AI model biases are constraints. Regulatory frameworks must be modified to ensure transparency, accountability, and compliance with AI-enhanced cryptography systems. This research shows that AI can strengthen blockchain transactions, indicating that AI and cryptography will shape safe and efficient financial systems in the future.

Jelena Ćeranić Perišić

The metaverse is a concept of cyberspace built on the existing infrastructure of the Internet using emerging technologies of blockchains, cryptocurrency and non-fungible tokens (NFT). In the metaverse, people and various forms of algorithms and artificial intelligence will interact in virtual reality, buy and sell “real world” and “in the metaverse” goods and services and get into legal disputes just like in real life. Trademark law has a decisive role in the development and protection of the brand in virtual reality. The paper first presents the notion of NFT. Then, the protection of trademark in metaverse is analyzed. Special attention is paid to the European Intellectual Property Office Guidelines from July 2022 on its approach to classifying virtual goods and NFTs. Finally, a case from US judicial practice is presented – Hermes Int’l v. Rothschild. This decision provides useful guidance on how courts will treat this issue in the future.

Mao Tian, Junhua Chen

Smart contract is presented as a new infrastructure for programming, deployment and execution with the rapid pace of blockchain technology in recent years. The development of blockchain technology provides a good operational basis for smart contracts, which can play an important role on the blockchain. With the rapid development of blockchain platforms such as bitcoin, smart contracts have a good opportunity for development. However, smart contract applications are still at an early stage of development, with relatively little relevant research, and the applicable scenarios of smart contracts in practical applications are not rich enough. In the paper, we study and discuss several aspects, by changing decentralization to weak-centralization, retaining appropriate supervision, and providing necessary right remedy for users of non-performance clause, can make smart contracts safe to use by compromising part of transaction efficiency.

Ellie Rennie

Abstract The survival of permissionless blockchains is typically cast as a cryptoeconomic security problem for mechanism designers to resolve. This essay argues that, long-term, these networks may require something that looks more like a UNESCO protection convention for machine culture than an equation. Ethereum’s machine culture is observable through the formation of a “’we’-group” (Hartley & Potts, 2014, p. 76), which is necessary for the establishment of common knowledge. While entry to the group is permissionless, maintaining membership boundaries demands active contributions from validator nodes. The paper discusses concerns that Ethereum’s consensus may be used for purposes beyond itself, making Ethereum vulnerable to external, non-machine political forces. As this begins to manifest, the need to safeguard Ethereum’s intrinsic machine culture becomes apparent—not merely for the sake of the blockchain but to maintain a stable foundation for emerging digital economies and governance structures.

Zeinab Shahbazi, Yung-Cheol Byun

Cryptocurrency, often known as virtual or digital currency, is a safe platform and a key component of the blockchain that has recently attracted much interest. Utilizing blockchain technology, bitcoin transactions are recorded in blocks that provide detailed information on all financial transactions. Artificial intelligence (AI) has significant applicability in several industries because of the abundance and processing capacity of large data. One of the main issues is the absence of explanations for AI algorithms in the current decision-making standards. For instance, there is no deep-learning-based reasoning or control for the system's input or output processes. More particularly, the bias for adversarial attacks on the process interface and learning characterizes existing AI systems. This study suggests an AI-based trustworthy architecture that uses decentralized blockchain characteristics such as smart contracts and trust oracles. The decentralized consensuses of AI predictors are also decided by this system using AI, enabling secure cryptocurrency transactions, and utilizing the blockchain technology and transactional network analysis. By utilizing AI for a thorough examination of a network, this system's primary objective is to improve the performance of the bitcoin network in terms of transactions and security. In comparison to other state-of-the-art systems, the results demonstrate that the proposed system can achieve very accurate output.

Nassim Dehouche, Richard Blythman

Intelligent human inputs are required both in the training and operation of AI systems, and within the governance of blockchain systems and decentralized autonomous organizations (DAOs). This paper presents a formal definition of Human Intelligence Primitives (HIPs), and describes the design and implementation of an Ethereum protocol for their on-chain collection, modeling, and integration in machine learning workflows.

Ryan Scheiding

The “metaverse” and non-fungible tokens (NFTs), though not necessarily “new” terms or technologies, have risen to mainstream prominence post-2020. This paper, based on survey data obtained from Unity Technologies, examines the metaverse, NFTs, and the future of development within the Unity engine from the perspective of current Unity users. Specifically, the paper examines how users define the metaverse, their goals in metaverse and NFT development, and their future questions and concerns concerning these concepts. This data is then used to place the metaverse and NFTs into broader historical, present, and future contexts. The paper ultimately argues: (1) the metaverse and NFTs follow previous historical trends in communication technology development, (2) development within Unity will continue to be split between game development and non-game development, and (3) arguments of the “newness,” “uniqueness,” or “future-facing” of the metaverse and NFTs help to obfuscate legitimate concerns about these technologies.

Jonas Oppenlaender

Smart contracts are a method for implementing direct democracy in virtual worlds. However, it is not clear whether voting preferences in the virtual world will mirror real-world voting preferences. We present a within-subject study in which participants were asked to allocate voting power in two scenarios. The first scenario probed participants’ opinion about the divisibility of voting rights. The second scenario presented participants with the case of unequal allocation of voting power in a virtual world, enforced by smart contracts. In both scenarios, participants allocated voting power and rated the fairness of their decision. Our study finds that participants’ voting preferences in the virtual world scenario did not mirror their real-world preferences and beliefs. Voting systems in the metaverse need to be carefully designed to align with human values and ethics.

Meghana Kshirsagar, Gauri Vaidya, Yao Yao, Smita Kasar · 5 authors

Abstract Health care interoperability unfolds the way for personalized health care services at a reduced cost. Furthermore, a decentralized system holds the promise to prevent compromises such as cyber‐attacks due to data breaches. Hence, there is a need for a framework that seamlessly integrates and shares data across the system stakeholders. We propose SEquestered aNd SynergIstic BLockchain Ecosystem (SENSIBLE), a blockchain‐powered, knowledge‐driven data‐sharing framework that gives patients complete control of their medical history and can extract rich information hidden in it using knowledge graphs (KGs). By incorporating both blockchain and KGs, we can provide a platform for secure data sharing among stakeholders by maintaining data privacy and integrity through data authentication and robust data integration. We present a Proof‐of‐Concept of the SENSIBLE network with Ethereum to share dynamic knowledge across stakeholders. Dynamic knowledge generation on the blockchain provides a two‐fold advantage of cooperation and communication amongst the stakeholders in the health care ecosystem. This leads to operational ease through sharing relevant portions of complex information while also ensuring the isolation of sensitive medical data.

Rahime Belen-Saglam, Enes Altuncu, Yang Lü, Shujun Li

The blockchain technology has been rapidly growing since Bitcoin was invented in 2008. The most common type of blockchain systems, public (permisionless) blockchain systems have some unique features that lead to a tension with European Union's General Data Protection Regulation (GDPR) and other similar data protection laws. In this paper, we report the results of a systematic literature review (SLR) on 114 research papers discussing and/or addressing such a tension. To be the best of our know, our SLR is the most comprehensive review of this topic, leading a more in-depth and broader analysis of related research work on this important topic. Our results revealed that three main types of issues: (i) difficulties in exercising data subjects' rights such as the `right to be forgotten' (RTBF) due to the immutable nature of public blockchains; (ii) difficulties in identifying roles and responsibilities in the public blockchain data processing ecosystem (particularly on the identification of data controllers and data processors); (iii) ambiguities regarding the application of the relevant law(s) due to the distributed nature of blockchains. Our work also led to a better understanding of solutions for improving the GDPR compliance of public blockchain systems. Our work can help inform not only blockchain researchers and developers, but also policy makers and law markers to consider how to reconcile the tension between public blockchain systems and data protection laws (the GDPR and beyond).

Ümit Cali, Md Sadek Ferdous, Enis Karaarslan, Sri Nikhil Gupta Gourisetti · 5 authors

As the global industrial complex gears toward fulfilling the tenets of Industry 4.0 and beyond, technologies such as distributed ledger technologies, digital twins, and artificial intelligence become pivotal enablers. In the last decade, metaverse as a concept and technology found its place among crucial enablers for technology and digital advancement across several engineering domains. Metaverse has the potential to combine the elements from distributed computing platforms, the digital evolution of physical systems, and advanced learning systems to unearth a fully digitized world of comparative properties of the real world. We should ensure the privacy, integrity, and confidentiality of personal data. These requirements will lead to proper identity management in the metaverse. Given the complex nature of the metaverse, traditional centralized systems may not offer a viable identity management solution. Therefore, this study explores a decentralized identity management system called the Self-sovereign Identity (SSI) as a logical alternative to traditional centralized identity management systems. The proposed holistic framework aims to ignite new ideas and discussions related to the combined deployment of DLT, SSI, and metaverse to inspire new implementation areas within the Industry 4.0 environment. The paper also discusses various opportunities, enablers, technical \& privacy aspects, legislation requirements, and other barriers related to SSI implementation.

Senou Mahugnon Rosaire, Jules Dégila

Blockchain-enabled smart contracts are subjected to several issues leading to vigorous attacks such as the decentralized autonomous organization (DAO) and the ParitySig bug on the Ethereum platform with disastrous consequences. Several solutions have been proposed. However, new threats are identified as technology evolves and new solutions are produced, while some older threats remain unsolved. Thus, the need to fill the gap with a more comprehensive survey on existing issues and solutions for researchers and practitioners arises. The resulting updated database will become an essential means for choosing a particular solution for a specific subject. In this review, the authors embrace mainly codifying security privacy and performance issues and their respective solutions. Each problem is attached to its corresponding solutions when they exist. A summary of the threats and solutions is provided as well as the relationship between threat importance and the given answers. They finally enumerate some directives for future works.

Roberto Garcı́a, Ana Cediel, Mercè Teixidó, Rosa Gil

Recent initiatives related to the Metaverse focus on better visualization, like augmented or virtual reality, but also persistent digital objects. To guarantee real ownership of these digital objects, open systems based on public blockchains and Non-Fungible Tokens (NFTs) are emerging together with a nascent decentralized and open creator economy. To manage this emerging economy in a more organized way, and fight the so common NFT plagiarism, we propose CopyrightLY, a decentralized application for authorship and copyright management. It provides means to claim content authorship, including supporting evidence. Content and metadata are stored in decentralized storage and registered on the blockchain. A token is used to curate these claims, and potential complaints, by staking it on them. Staking is incentivized by the fact that the token is minted using a bonding curve. The tokenomics include the resolution of complaints and enabling the monetization of curated claims. Monetization is achieved through licensing NFTs with metadata enhanced by semantic technologies. Semantic data makes explicit the reuse conditions transferred with the token while keeping the connection to the underlying copyright claims to improve the trustability of the NFTs. Moreover, the semantic metadata is flexible enough to enable licensing not just in the real world. Licenses can refer to reuses in specific locations in a metaverse, thus facilitating the emergence of creative economies in them.