Blockchain Papers

Daniel Blaseg

No abstract is available for this record.

Hallvard Kristoffer Boland Haugen, Andreas Fougner Engebretsen

The topic of revenue streams in the music industry has been frequently discussed since the transition from sales to streaming started when Spotify launched in 2008. Even though revenues in the industry have reached new heights, musicians express dissatisfaction with lower royalty payouts. Moreover, it has become increasingly more difficult to understand the royalty calculations. With today's complicated licensing agreements, money flows through a complex chain of third parties before it reaches the musicians. The industry struggles with transparency and efficiency, and the musicians are paying the price. Meanwhile, blockchain technology has developed since its first implementation with Bitcoin in 2008. Today, more advanced blockchains can run decentralized transparent applications that utilize the technology's efficient transaction system. With the industry issues and the promises of blockchain in mind, we investigate how blockchain technology can be applied to solve value chain problems within the music space.\n\nIn this thesis, we identify core issues in the music industry, propose a decentralized application (dApp) that attempts to solve these issues and implement the proposed solution. We develop the business logic using smart contracts on the Ethereum blockchain and make an associated web application using a JavaScript framework. The dApp works as a global copyrights database where musicians can register and license musical works. We exploit Ethereum's efficient transactional system to manage license purchases. Furthermore, we discuss the advantages and disadvantages of blockchain based solutions.

Lauren Rhue

No abstract is available for this record.

Thorsten V. Koeppl, Jeremy Kronick

No abstract is available for this record.

Michael Graham, Igor Dosen

No abstract is available for this record.

Julian Yu, Benjamin Yen

Modern insurance has been operating in the same business model since its inception while its recent IT improvement is mainly for specific functions without overall structural review. This paper is to incorporate the concept of a cryptocurrency, called Risk Coin, as the foundation of a new model to enhance the risk financing efficiency with capital market. Risk Coin is 1) a shareholding token of the premium fund with benefits from law-of-large-numbers, and 2) a cryptocurrency with benefits from seigniorage as fiat currency anchored at value of coin fund formed by collected premium and refund from loss payments. Applications in current insurance environment of pipeline model as well as in an innovative environment of platform model are simulated. Both results show a self-balancing mechanism that higher coin value from less coin preference, therefore, encouraging coin receivers to keep coins. Overall the new model will enhance the effectiveness of risk funding by keeping risk coins and also turn insurance deal to a win-win situation form zero-sum game through premium payment as gaining ownership of risk fund.

matthew baldree, paul widhalm, brandon hill, Matteo Ortisi

In this paper, we present a tool that provides trading recommendations for cryptocurrency using a stochastic gradient boost classifier trained from a model labeled by technical indicators. The cryptocurrency market is volatile due to its infancy and limited size making it difficult for investors to know when to enter, exit, or stay in the market. Therefore, a tool is needed to provide investment recommendations for investors. We developed such a tool to support one cryptocurrency, Bitcoin, based on its historical price and volume data to recommend a trading decision for today or past days. This tool is 95.50% accurate with a standard deviation of 0.54%. From our analysis, we conclude that Bitcoin is a unique asset with similarities to gold. As a young asset, it lacks economic fundamentals making it very difficult to predict. By leveraging technical momentum indicators to provide buy, sell, and hold markers or labels, a tool can be developed that performs as good or better than a buy and hold trading strategy in a bear market, bull market or both markets.

Bo Zhao, Peiru Fan, Mingtao Ni

Virtual machine (VM) measurements data in IaaS cloud play a crucial role in integrity evaluation and decision making. Hence, the secure storage for these data has attracted more attention recently. This paper proposes a novel approach, named Mchain, to enhance the integrity and controllability of the secure storage. Especially, to enhance the integrity, a two-layer blockchain network is introduced. In the first layer, after the production, the data packages are first verified by leveraging a correspondence between a package and a policy, and a one-to-one relation among a VM, a user, and a node. After that, we propose a consensus achievement algorithm to construct a semi-finished block on a candidate block arranged by data packages. Meanwhile, the semi-finished block is distributed to all nodes, which can provide a certain integrity. In the second-layer, tamper-resistant metadata is generated by performing PoW tasks on the semi-finished block, resulting in strong integrity. Further, to enhance the controllability, a revisable user-defined policy-based encryption method with KP-ABE is proposed. It helps to flexibly control the scope of authorized verifiers. The experimental results on six scenarios with simulated data set show that the proposed approach is appealing in integrity and controllability, and the time overhead of data storage.

Thomas E. Portegys

The latency and throughput of blockchain-based cyrptocurrencies is a major concern for their suitability as mainstream currencies and as transaction processors in general. The prevalent proof-of-work scheme, exemplified by Bitcoin, is a deliberately laborious effort: the time and energy required to mine blocks makes the blockchain virtually immutable and assists in the consensus-reaching process. Coinspermia (coin=money + spermia=seed) is a different approach: transactions are concurrently seeded throughout a network of peer nodes to an extent sufficient to achieve a high reliability of essential currency operations, including the fast transfer of coins from an owner to a recipient, and the prevention of double spending. A number of Bitcoin features are retained in Coinspermia, including transaction input-outputs and cryptographic addresses and signing, but no special proof-of-work is required to commit transactions. Instead, a client can be assured of an operation completion when a quorum of network nodes acknowledge the operation, which can occur before a transaction operation finishes propagating through the network. Simulation substantiates improved latency and throughput.

Carlo Armillis

No abstract is available for this record.

A. M. Bondarenko

Cryptocurrency is a new trend in business sphere all over the world.It gave us opportunities to earn, to produce, to sell.But the growth of popularity of it must be connected with understanding of its functioning, understanding of possibilities it gives us.According to statistics, there are hundreds Billion dollars invested in this sphere, which makes it worth our close attention, but misunderstanding, fake news and the lack of credible information arouses distrust and creates a gap between society and this budding sphere.The aim of this work is popularization and explanation of possibilities of earning, which are created by cryptocurrencies.

Peder Østbye

No abstract is available for this record.

Ashish Rajendra Sai, Jim Buckley, Andrew Le Gear

Proof Of Work Blockchains such as Bitcoin and Ethereum exhibit a low Transaction Per Second (TPS) that impacts the scalability of the blockchain. Manipulating the block creation time can yield a higher TPS. A lower block creation rate results in a higher Stale Block rate that has a direct impact on the security of blockchain. We intend on using a novel Proof of Work Classification model under a varying level of difficulty to classify an instance of blockchain with a threshold (Block-time) on the basis of it’s resilience to selfish mining and double-spending attacks. Use of an ideal block creation time can help Proof of Work blockchains scale and attain a higher TPS without trading off security. The classification model can further be extended to find an optimal block-size.

Σωτήριος Καραπέτσας

Με τις πρόσφατες εξελίξεις στις τεχνολογίες της πληροφορίας και της επικοινωνίας και την διαδεδομένη δημοτικότητα των κινητών τηλεφώνων (π.χ. συσκευών Android και iOS), οι ψηφιακές πληρωμές και τα κρυπτονομίσματα όπως το Bitcoin, το Litecoin, το Ethereum και άλλα, γίνονται ολοένα και πιο δημοφιλή στο ηλεκτρονικό εμπόριο.
\nΟι εγκληματίες - συχνά πρωτοπόροι των νέων τεχνολογιών - εκτίμησαν γρήγορα ότι το Bitcoin ως πρωτοπόρο, αλλά και τα λοιπά κρυπτονομίσματα στη συνέχεια, έχουν μοναδικές ιδιότητες που θα μπορούσαν ενδεχομένως να εξυπηρετήσουν το ενδιαφέρον τους για αποφυγή της επιβολής του νόμου.
\nΤο Bitcoin εισάγει μια σειρά προκλήσεων στις ψηφιακές έρευνες που οφείλονται κυρίως στα στοιχεία της ψευδωνυμίας που παρέχει σε ένα χρήστη και το αποκεντρωμένο δίκτυο μέσα στο οποίο λειτουργεί, όπου με τη χρήση του μπορεί να μεταφερθεί χωρίς μεσάζοντες ακόμη και σε διεθνή σύνορα τόσο εύκολα όσο και η αποστολή ενός μηνύματος ηλεκτρονικού ταχυδρομείου.
\nΑυτά τα χαρακτηριστικά το έχουν καταστήσει ελκυστικό μέσο ανταλλαγής για όσους ασχολούνται με εγκληματικές δραστηριότητες στο διαδίκτυο. Κατά το παρελθόν έχει χρησιμοποιηθεί για τη νομιμοποίηση εσόδων από παράνομες δραστηριότητες και για φοροαποφυγή, ενώ έχει χρησιμοποιηθεί εκτεταμένα για την αγορά παράνομων προϊόντων, αγαθών και υπηρεσιών μέσω διαδικτυακών αγορών, όπως το Silk Road στο Dark Web.
\nΧρησιμοποιήθηκε και χρησιμοποιείται επιπλέον από επίδοξους χάκερ ως τρόπος πληρωμής για επιθέσεις ransomware που έχουν σημειώσει τεράστια ανάπτυξη κατά τη διάρκεια των τελευταίων χρόνων από την δημιουργία του.
\nΠαρά το γεγονός ότι το Bitcoin αλλά και τα άλλα εικονικά νομίσματα (κρυπτονομίσματα) αποτελούν πηγή αποδεικτικών στοιχείων, έχει υπάρξει περιορισμένη έρευνα στην εγκληματολογική εξέταση τους. Η υπάρχουσα εγκληματολογική έρευνα σχετικά με το Bitcoin επικεντρώνεται κυρίως στο Blockchain (το καθολικό ledger στο οποίο καταγράφονται οι συναλλαγές) και όχι στο Bitcoin, ως λογισμικό του χρήστη (π.χ. την εφαρμογή πορτοφολιού για κινητά τηλέφωνα) προκειμένου να βρεθούν και να ανακτηθούν δεδομένα σχετικά με τις συναλλαγές που έχει πραγματοποιήσει ένας χρήστης χρησιμοποιώντας την συγκεκριμένη εφαρμογή ή και άλλα στοιχεία που σχετίζονται με την συμπεριφορά του χρήστη κατά την χρήση της εφαρμογής πορτοφολιού Bitcoin. Αυτό είναι το κενό που επιδιώκουμε να αντιμετωπίσουμε σε αυτή την εργασία.

Ala Rahma Hanchi

Genomgår pengar en revolution? Ett mycket centralt ämne i ekonomi är pengar, pengar har genomgått många utvecklingar och därmed har även synen på pengar förändrats över tid. Vi har använt varor och råvaror som pengar. En bytesekonomi där snäckor, stenar och fjädrar ansågs vara värdefulla att handla med, för att sedan övergå till dyrbara metaller som guld och silver. Denna övergång utvecklades och vi fick våra första sedlar som tillverkade i Kina, därefter tillkom papperssedlar, kreditkort och digitala pengar. Nu har det uppkommit en ny typ av valuta på marknaden som kan innebära nästa steg i utvecklingen. Nämligen kryptovalutan, som är omfattande för alla digitaliserade valutor, men valutan kan också vara decentraliserad. Den virtuella valutan har många kritiker, men användningen av valutan fortsätter att expandera. Bitcoin är den första och mest använda kryptovalutan (Bitcoin, 2018). Syftet med denna studie är att genom intervjuer med fem Bitcoin investerare förstå vad som är värdeskapande och att dessutom förstå vilka fördelar och nackdelar den virtuella valutan Bitcoin har för sina investerare. Värdeskapande är subjektivt och sker i samband med att investerare interagerar med varandra. Investerare i Bitcoin menar att det som är värdeskapande är sex faktorer: lönsamhet, risk, tillit, överförbarhet och transparens, säkert och kontroll samt kontroverser.

Fredrik Mörtberg

With increasing popularity, the scalability of blockchain-based crypto-currencies becomes an urgent concern. Bitcoin, among other crypto-currencies, have known limitations in transaction throughput and speedbut no agreed upon solution. Many of the proposals increasing throughput also increase the load on the Bitcoin network. Lightning is a proposal enabling payments to be conducted without affecting the Bitcoin network. Lightning is a protocol using payment channels to enable instant and cheap payments using the blockchain for security. With Lightning, payments can be sent through a network of nodes connected by payment channels. In this thesis, the current state of Lightning is explored and an evaluation for use on Bitcoin exchanges is performed. The usability, privacy and security of Lightning are the topics evaluated. In order to evaluate the usability, an exchange interface application was built allowing deposits and withdrawals using Lightning. The protocol specification and relevant literature are examined in order to evaluate the security and privacy of Lightning. The exchange interface showed that Lightning can be integrated into an exchange and provide a fast and cheap way to deposit and withdraw money for clients. In this paper some integration designs are proposed and ways to improve the client user experience are discussed. The Lightning node implementations need to mature a bit before real usage and there are some security issues that also need to be considered. With monitoring and network analysis the privacy can be compromised.

Christian Catalini, Catherine E. Tucker

No abstract is available for this record.

Daniel Fredén, Simon Norell

Since the current cryptocurrencies has failed to reach the level of normality of standard fiat currencies and banking systems there exist a need for a new cryptocurrency if this shall ever be the case. This project will be a part of creating and designing such a cryptocurrency that hope to compete with the fiat currencies of our time. This with the following research question: In the examined network, would increasing the reward received by the participants who successfully validate a transaction result in faster validation time and thereby faster transactions? This question is examined with basis in game theory and simplified simulations to be able to draw conclusions about how the network behaves. Conclusions such as when the participants increases the system speed decreases or that when the money in the system increases there exist an incentive for the participants to work faster. Possible Nash equilibriums are also examined to guide the participants when deciding strategies. Since the purpose of this project is to create a cryptocurrency that can compete with fiat currencies a short comparison between cryptocurrencies and fiat currencies are discussed.

Vincenzo Ferrari, João Pedro Quintais, Αλεξάνδρα Γιαννοπούλου, Balázs Bodó

The EU Blockchain Observatory and Forum (an initiative led by DG CONNECT) organized the “Workshop on GDPR, data policy and compliance” event in June 2018 to discuss data protection issues as well as privacy-enhancing features of blockchain technologies. The meeting gathered stakeholders and experts to examine the main challenges and opportunities of distributed ledger technologies (DLTs), so supporting the European Commission’s efforts to provide practical guidelines for the industry. Ms. Valeria Ferrari, of the Blockchain & Society Policy Research Lab participated in the workshop, and compiled this report.

Michael Crystal

No abstract is available for this record.

Rishi Broto Chakraborty, Manjusha Pandey, Siddharth Swarup Rautaray

This paper proposes optimization mechanisms for a multi – layered IoT network model, backed up by Blockchain Technology. This paper focuses on optimizing the computational load such that the model can meet the feasible conditions for deployment purpose. Though, dividing the IoT network into multiple layers reduces the computational load at each stage, the load split isn’t quite proportional to the amount of work done at each level. Flexibility to monitor computational load at each level and distribute the workload has been introduced at each level.

Purvee Pareek Gaur

No abstract is available for this record.

Magda Foti, Manolis Vavalis

This paper considers the design, the developed and the experimental evaluation, a blockchain based smart contract specifying the operating rules of a real time, uniform-price double auction energy market. Producers and consumers interact with this contract sending their offers and bids accordingly and the contract clears the market based on a double auction model. We propose four different approaches for implementing, through the Ethereum platform, both the P2P network as well as the smart contract. We systematically compare the above approaches on the basis of their decentralization nature, operating costs, computational costs, effectiveness, security, privacy and beyond. This comparison is achieved through large scale, real time simulations based on the GridLAB-D platform.

Authors unavailable

Bitcoin is a digital currency raised by Satosghi Nakamoto, which is Completely decentralized, Highly anonymous, cross-border. Nowadays it has became one of the most widely used currency. Recently, as the used capacity has approached the capacity limitation of each block, the time needed to confirm a transaction increase dramatically. As a result, bitcoin cannot satisfy the need of a large number of bitcoin transactions. This paper aims to apply merged mining technology to bitcoin blockchain scaling, which builds another blockchain called auxiliary blockchain based on bitcoin blockchain and stores some of small rapid transactions in auxiliary blockchain. This paper also proves the merged mining technology can concentrate computing power and design a special miner reward program.