Blockchain Papers

Ibrahim Shehata

No abstract is available for this record.

Min Luo, Vasileios E. Kontosakos, Athanasios A. Pantelous, Jian Zhou

No abstract is available for this record.

Veskus, Karl

Käesolevas bakalaureusetöös tutvustatakse plokiahela tehnoloogiat ning selle kahte erinevat platvormi, Ethereum ja Hyperledger Fabric, mis on loodud väga erinevate rakenduste loomiseks kasutades just plokiahela tehnoloogiat. Peale selle luuakse mõlemat platvormi kasutades sarnane rakendus, millele järgneb võrdlus. Esiteks, annab võrdlus lugejale ülevaate, kuidas antud platvormid üksteisest arhitektuuri ning kasutajamugavuse poolest erinevad. Teiseks näitab, kuidas erineb nende platvormide abil rakenduste loomine ning mille poolest erinevad lõputöö raames loodud rakendused.

Ιωάννης Μιχαήλ, Ioannis Michail

Throughout the history of mankind, trusted relationships have played a vital part in every
\ntransaction humans have made. Those transactions belong to a spectrum that starts from
\neveryday life decisions and acts, to a more complex, sensitive and wide area that even nations
\nare involved.
\nBefore the era of globalization of telecommunications that we live in, achieving trust was
\nmore related to human relations. Even though that the meaning of trust is known to all, it is
\nhard to find a definition that strictly describes it.
\nTrust is multidimensional, multidisciplinary and multifaceted concept. Many definitions can
\nbe found in literature and are related to notions as goodness, strength, reliability, integrity,
\nability or character of a person or thing. A trust relationship involves two parties, a trustor
\nand a trustee. The trustor is the person that holds confidence, belief on the reliability of
\nanother person or thing which is the other party, the trustee. (Zheng & Valtteri Niemi,
\nTowards User Driven Trust Modeling and Management, 2009)
\nHow though trust is established in modern computer networks, where the notions of the
\ntrustor and trustee are not represented by strictly humans, but from entities that might never
\nhave had a relationship upon the trust can be build.
\nIn this project we will study the achievement of trust in traditional kinds of networks such as
\nad-hoc, mobile and wireless and we will examine the ability to elevate the trust level in a
\ncomputer network using the under development and mostly promising blockchain network.
\nThe network is going to be setup as a private blockchain network, where all the nodes that
\nconsist it, will be pre-set from an administrative team. The computers that will participate will
\nhave all the requirements in order to connect to the private network running as services on
\nboot.
\nThe application will run on each node and on starting the application the very first check will
\nbe to start the node and connect to the network. Only if the network has been found and the
\nnode is connected to it, the application proceeds with checking the presence of web3js and
\nonly after successfully checking the communication of the web3js with the network, the user
\nis prompt with the login page.
\nThe authorization of the user is checked upon a smart contract on the blockchain network
\nand after a successfully prompt from the smart contract, the credentials are checked, in our
\ncase, on a fake backend where a JWT token is issued to the user in order to use the application
\ndepending on the role that he has.

André Caldegren

Cryptocurrencies are a cryptography based technology, that has increased massively in popularity in recent years. These currencies are traded on markets that specialize in cryptocurrency trade. There, you can trade one cryptocurrency for another, or buy one with real world money. These markets are quite volatile, meaning that the price of most cryptocurrencies swing up and down a lot. The largest cryptocurrency is Bitcoin, but there is also more than 1500 smaller ones, that goes by the name alternative coins, or altcoins. This thesis will try to find out if it is possible to make accurate predictions about the future price of the altcoin Ethereum, and also see if Bitcoin may have some influence over the price of the selected altcoin. The predictions were made with the use of an artificial neural network, an LSTM network, that was trained on labeled data from 2017. The predictions were then made in intervals of one hour ahead, six hours ahead, and one day ahead through early 2018. The predictions showed that it is possible to make somewhat accurate predictions about the future. The predictions that were made one hour ahead were more accurate than both the six hours ahead predictions and the full day ahead predictions. By comparing the loss rates of the neural networks that were only trained on Ethereum, with the loss rates of the networks that trained on both Bitcoin and Ethereum, is was made clear that training on both cryptocurrencies did not improve the prediction accuracies.

Jens Röwekamp

The scandal around Facebook and Cambridge Analytica in 2017 showed drastically that new concepts to share andstore information need to be developed in order to minimize the huge potential for abuse resulting from centralized information stored at trusted third parties. This thesis analysed to what degree current document exchange systems (e.g. Dropbox) comply with the information security services confidentiality, integrity, privacy, anonymity, authenticity of authors, non-repudiation, and accountability; with the result that all analysed systems lack support for privacy and anonymity. Mainly due to their centralized design, missing (meta)data encryption, and regulations of jurisdictions in which they operate. Based on that analysis a decentralized concept for document sharing in a peer-to-peer fashion utilising client-side encryption, the separation of data and metadata, metadata masking through Tor hidden services, and distributed ledger technology for directory service provision, was developed. The concept was proven through prototype implementation of a document exchange software called docShare and its information security services were compared with former analysed exchange technologies. The analysis showed that docShare has a better information security service provision but is still leaking identity information in form of IPad dresses when interacting with the distributed ledger Ethereum. Mainly because Ethereum doesn’t support traffic anonymization through Tor.

Mahawuya Kabuye

No abstract is available for this record.

Jérémy Charlier, Radu State, Jean Hilger

Background: Past few months have seen the rise of blockchain and cryptocurrencies. In this context, the Ethereum platform, an open-source blockchain-based platform using Ether cryptocurrency, has been designed to use smart contracts programs. These are self-executing blockchain contracts. Due to their high volume of transactions, analyzing their behavior is very challenging. We address this challenge in our paper. Methods: We develop for this purpose an innovative approach based on the non-negative tensor decomposition Paratuck2 combined with long short-term memory. The objective is to assess if predictive analysis can forecast smart contracts activities over time. Three statistical tests are performed on the predictive analytics, the mean absolute percentage error, the mean directional accuracy and the Jaccard distance. Results: Among dozens of GB of transactions, the Paratuck2 tensor decomposition allows asymmetric modeling of the smart contracts. Furthermore, it highlights time dependent latent groups. The latent activities are modeled by the long short term memory network for predictive analytics. The highly accurate predictions underline the accuracy of the method and show that blockchain activities are not pure randomness. Conclusion: Herein, we are able to detect the most active contracts, and predict their behavior. In the context of future regulations, our approach opens new perspective for monitoring blockchain activities.

Yanqi Zhao, Yannan Li, Qilin Mu, Bo Yang · 5 authors

The cyber physical system (CPS) has gained considerable success in large-scale distributed integration environment. In such systems, the sensor devices collect data which would be disseminated via reliable manner to all interested co-operant entities from the physical world. However, highly unreliable environment of CPS, for example, a number of limitations of existing network middle wares, makes secure and reliable data distribution services a challenge issue. In this paper, we propose a new architecture called secure pub-sub (SPS) without middle ware, i.e., blockchain-based fair payment with reputation. In SPS, publishers publish a topic on the blockchain and subscribers specify an interest message by making a deposit to subscribing the topic. Then, if the interest message matches the topic, the publisher transmits the encrypted content of the topic to the blockchain such that the subscribers can decrypt the ciphertext to obtain the content, and mark the publisher as its reputation. Finally, the publisher receives the payment from the subscriber. The new proposal provides confidentiality and reliability of data, anonymity of subscribers and payment fairness between the publishers and subscribers. Different from the traditional pub-sub services, no trusted third party is involved in our system due to employing blockchain technique. The security of the proposed SPS is analyzed as well. The implementation of the protocol on Ethereum of smart contract demonstrates the validity of SPS.

Joseph Wall, D. Larry Crumbley, Lewis B. Kilbourne, Caleb Blair

In this report, the authors discuss cryptocurrencies — especially bitcoin — and argue that because the IRS lists them as property, they are taxable, and because they are not as anonymous as once thought, they are not free from fraud. Cryptocurrencies are digital assets used as a medium of exchange, but they are not really coins. They can be sent electronically from one entity to another almost anywhere in the world with an internet connection. There are many cryptocurrencies in the market, including bitcoin, ethereum, ethereum classic, litecoin, nem, dash, iota, bitshares, monero, neo, and ripple. Many of the cryptocurrency networks are not controlled by a single entity or company; instead, a decentralized network of computers keeps track of the currency using a token ID. A ledger maintains a continuously growing list of date stamped transactions in real time called “blocks.” This technology is known as blockchain, which records, verifies, and stores transactions without a trusted central authority. The network instead relies on decentralized autonomous organizations (DAOs) with uncertain legal standing.

Urban J. Jermann

No abstract is available for this record.

Jonathan Taylor Heinecke

Distributed ledger technologies (DLTs) are currently dominating the field of distributed systems research and development. The Ethereum blockchain is emerging as a popular DLT platform for developing software and applications. Several challenges in Ethereum software development are the complex nature of working with DLTs, the lack of tools for developing on this DLT, and poor documentation of concepts for DLT developers. In this thesis, we provide building blocks that reduce the complexity of DLT operations and lower the barrier to entry into DLT development. We do this by providing a Node.js library, Ethereum-Easy, that simplifies operations on Ethereum. We implement this library into a sample application called Rock, Paper, Scissors (RPS) and built a continuous delivery, continuous integration pipeline for deploying Ethereum code (Jenk-Thereum). This thesis aims to make development on DLTs easier, quicker, and less expensive.

Gaby G. Dagher, Praneeth Babu Marella, Matea Milojkovic, Jordan Mohler

Voting is a fundamental part of democratic systems; it gives individuals in a community the faculty to voice their opinion. In recent years, voter turnout has diminished while concerns regarding integrity, security, and accessibility of current voting systems have escalated. E-voting was introduced to address those concerns; however, it is not cost-effective and still requires full supervision by a central authority. The blockchain is an emerging, decentralized, and distributed technology that promises to enhance different aspects of many industries. Expanding e-voting into blockchain technology could be the solution to alleviate the present concerns in e-voting. In this paper, we propose a blockchain-based voting system, named BroncoVote, that preserves voter privacy and increases accessibility, while keeping the voting system transparent, secure, and cost-effective. BroncoVote implements a university-scaled voting framework that utilizes Ethereum’s blockchain and smart contracts to achieve voter administration and auditable voting records. In addition, BroncoVote utilizes a few cryptographic techniques, including homomorphic encryption, to promote voter privacy. Our implementation was deployed on Ethereum’s Testnet to demonstrate usability, scalability, and efficiency.

Tiffany L. Minks

No abstract is available for this record.

Haya R. Hasan, Khaled Salah

With the widespread of E-commerce, the need of a trusted system to ensure the delivery of traded items is crucial. Current proof of delivery (PoD) systems lacks transparency, traceability, and credibility. These systems are mostly centralized and rely on trusted third parties (TTPs) to complete the delivery between sellers and buyers. TTPs can be costly, a single point of failure, and subject to hacking, privacy evasion, and compromise. The blockchain is an immutable, trusted, and decentralized ledger with logs and events that can be used for transparency, traceability, and tracking. In this paper, we present a solution and a general framework using the popular permissionless Ethereum blockchain to create a trusted, decentralized PoD system that ensures accountability, auditability, and integrity. The solution uses Ethereum smart contracts to prove the delivery of a shipped item between a seller and a buyer irrespective of the number of intermediate transporters needed. In our proposed solution, all participating entities are incentivized to act honestly by using a double deposit collateral. Automated payment in ether is an integral part of a solution to ensure that every entity gets its intended share of ether upon successful delivery. An arbitration mechanism is also incorporated if a dispute arises during the shipping process. In this paper, we show how we implemented, verified, and tested the proper functionality of our PoD solution. We also provide security analysis and give estimates of the cost consumption in ether gas. We made the full code of the Ethereum smart contracts publicly available at Github.

Jia Kan, Lingyi Zou, Bella Liu, Xin Huang

In recent years, with the rapid development and popularization of BitCoin, the research of blockchain technology has also shown growth. It has gradually become a new generation of distributed, non-centralized and trust-based technology solution. However, the blockchain operation is expensive and transaction is delayed. Take BitCoin as an example. On the one hand, a block is produced every ten minute. On the other hand, once the new block is generated, it takes a certain time to propagate world wide. The slow speed of propagation determines that BitCoin can not use too small block interval time. Ethereum also faces similar problems, so the concept of uncle block was introduced to reduce blockchain forks. This paper introduces a new tree structure based broadcast propagation routing model, providing a novel method to organize network nodes and message propagation mechanism. In oder to avoid the single node failure problem, the tree cluster routing is proposed. The research shows that the tree based routing can accelerate broadcast convergence time and reduce redundant traffic.

Thach Ngoc Nguyen, Christian Servín, Владик Крейнович

Nowadays, most financial transactions are based on a centralized system, when all the transaction records are stored in a central location. This centralization makes the financial system vulnerable to cyber-attacks. A natural way to make the financial system more robust and less vulnerable is to switch to decentralized currencies. Such a transition will also make financial system more transparent. Historically first currency of this type -- bitcoin -- use a large amount of electric energy to mine new coins and is, thus, not scalable to the level of financial system as a whole. A more realistic and less energy-consuming scheme is provided by proof-of-stake currencies, where the right to mint a new coin is assigned to a randomly selected user, with probability depending of the user's stake (e.g., his/her number of coins). What probabilities should we choose? In this paper, we find the probability selection that provides the optimal result -- optimal in the sense that it is the least inductive to cheating.

Nikos Fotiou, Vasilios A. Siris, George C. Polyzos

Despite technological advances, most smart objects in the Internet of Things (IoT) cannot be accessed using technologies designed and developed for interacting with powerful Internet servers. IoT use cases involve devices that not only have limited resources, but also they are not always connected to the Internet and are physically exposed to tampering. In this paper, we describe the design, development, and evaluation of a smart contract-based solution that allows end-users to securely interact with smart devices. Our approach enables access control, Thing authentication, and payments in a fully decentralized setting, taking at the same time into consideration the limitations and constraints imposed by both blockchain technologies and the IoT paradigm. Our prototype implementation is based on existing technologies, i.e., Ethereum smart contracts, which makes it realistic and fundamentally secure.

Bingsheng Zhang, Roman Oliynykov, Hamed Balogun

A treasury system is a community-controlled and decentralized collaborative decision-making mechanism for sustainable funding of blockchain development and maintenance. During each treasury period, project proposals are submitted, discussed, and voted for; top-ranked projects are funded from the treasury. The Dash governance system is a real-world example of such kind of systems. In this work, we, for the first time, provide a rigorous study of the treasury system. We modelled, designed, and implemented a provably secure treasury system that is compatible with most existing blockchain infrastructures, such as Bitcoin, Ethereum, etc. More specifically, the proposed treasury system supports liquid democracy/delegative voting for better collaborative intelligence. Namely, the stake holders can either vote directly on the proposed projects or delegate their votes to experts. Its core component is a distributed universally composable secure end-to-end verifiable voting protocol. The integrity of the treasury voting decisions is guaranteed even when all the voting committee members are corrupted. To further improve efficiency, we proposed the world's first honest verifier zero-knowledge proof for unit vector encryption with logarithmic size communication. This partial result may be of independent interest to other cryptographic protocols. A pilot system is implemented in Scala over the Scorex 2.0 framework, and its benchmark results indicate that the proposed system can support tens of thousands of treasury participants with high efficiency.

Nashirah Abu Bakar, Sofian Rosbi

The purpose of this study is to develop robust estimation of association between two types of crypto-currencies namely Bitcoin and Ethereum. Daily data of crypto-currencies are collected from https://coinmarketcap.com. The period for data analysis is started from January 2017 until October 2018. The value of mean return for Bitcoin is 13.18 %. Meanwhile, the value of mean return for Ethereum is 27.85 %. The standard deviation for Bitcoin is 30.27 % and Ethereum is 64.24 %. Then, this study performed Person product moment coefficient analysis to evaluate the correlation between these two crypto-currencies. Result indicates the association coefficient value is 0.50. The correlation shows there is strong positive correlation between Bitcoin return and Ethereum return. As conclusion, there is significant relationship between Bitcoin and Ethereum return data with strong positive correlation (r = 0.503, n = 21, p =0.020).The significant of this study is to help investors to make better decision in selecting appropriate investment portfolio for their investment fund that contributes better return and lower risk.

Pavan N. Kunchur, Prasad Pujar, Khasgatesh Hiremath, Amodh Budnimath · 6 authors

The advancements of AI techniques and its transformation made an intelligent automated process using Internet of Things (IoT), machine optimization in various industrial applications. One of the notable change happens in the healthcare industry witnessed significant progress, leading to the emergence of Health 4.0. This new era encompasses a wide range of cutting-edge technologies including the Internet of Things (IoT), Internet of Services (IoS), Medical Cyber-Physical Systems (CPS), Health Cloud, Health Fog etc. The largest barrier to electronic healthcare is securing all medical equipment that are connected to the internet. Blockchain, a distributed and immutable ledger or database, has gained popularity across various sectors, including healthcare, due to its efficiency and reliability by offering features such as decentralization, enhanced security, and immutability. This chapter aims to explore the advantages and challenges associated with implementing blockchain technology in healthcare 4.0 by providing factual evaluation of block chain's progress in healthcare.

Kuo‐Hui Yeh, Chunhua Su, Jia-Li Hou, Wayne Chiu · 5 authors

Recently, the popularity and universality of smart-devices has led to rapid advancement in the development of applications for mobile commerce around the world. Novel mobile payment schemes, such as Apple pay, Android pay, and Samsung pay are becoming an increasingly popular ways to conduct online transactions, no matter what type of smart devices are used. Due to the attendant growth in the importance of security, significant attention has been devoted to the challenge of designing and implementing a robust mobile payment scheme for securing online transactions. In this paper, we demonstrate a robust mobile payment scheme based on sturdy certificateless signatures with bilinear pairing. We elegantly refine the proposed mobile payment scheme to make it suitable for computation-constrained mobile devices. The practicability of the proposed mobile payment scheme is then certified via a rigorous security analysis and thorough performance evaluation using the Raspberry PI as the implementation platform for our proposed scheme. Furthermore, we implement a transaction repository with the aid of smart contract technology. The simulation results, based on Ethereum, demonstrate the feasibility of employing the smart contract technology to secure mobile payments.

Tiffany L. Minks

In a world full of new technology, the risk of fraud is constantly increasing. In the securities industry, this risk existed long before the use of technology. Congress enacted the Securities Act of 1933 to combat the risk of fraud and misrepresentation in the sale of securities. By requiring full disclosure, investors have the opportunity to make informed decisions prior to investing. However, Distributed Autonomous Organizations (“DAOs”), through the use of blockchains and smart-contracts, engage in the sale of securities without fully disclosing the risks or complying with the registration requirements of the Securities Act of 1933. Compliance with the burdensome requirements of registration, however, would destroy this new technology and method of conducting business. To avoid this set-back, Congress must amend the registration requirements to provide an exemption for DAOs. This exemption, although reducing current registration burdens, must still require DAOs to disclose certain information, thereby ensuring investors are informed prior to investing. Furthermore, due to the unique nature of the blockchain, smartcontract, and DAOs, Congress must impose a fiduciary duty on the creators of DAOs to ensure compliance with the disclosure requirements. Further, Congress should consider the allowance of burden-shifting following the initial crowdsale.

Sina Rafati Niya, Florian Schüpfer, Thomas Bocek, Burkhard Stiller

Abstract This work introduces the design and implementation of an Android-based Peer-to-peer Purchase and Rental Application termed PuRSCA, which leverages Smart Contracts (SC) and the Ethereum public blockchain (BC). As a Device-to-device (D2D) communication protocol, WiFi-Direct is chosen to enable the P2P data transmission between two parties. This work results in a cost-efficient, secure, SC-based, P2P, and Decentralized application (Dapp). Evaluations on performance of this Dapp is specified in terms of its D2D deployment, transaction costs, scalability, security, and privacy.