Blockchain Papers

Mikayla Novak

No abstract is available for this record.

J. Stuart Nelson

No abstract is available for this record.

Kunal Saha

No abstract is available for this record.

Neeraj Samtani

No abstract is available for this record.

Lin William Cong, Zhiguo He, Jiasun Li

The rise of centralized mining pools for risk sharing does not necessarily undermine the decentralization required for permissionless blockchains: Each individual miner's cross-pool diversification and endogenous fees charged by pools generally sustain decentralization, because larger pools better internalize their externality on global hash rates, charge higher fees, attract disproportionately fewer miners, and thus grow more slowly. Instead, mining pools as a financial innovation escalate the arms race among competing miners and thus significantly increase the energy consumption of proof-of-work-based consensus mechanisms. Empirical evidence from Bitcoin mining supports our model predictions. The economic insights inform many other blockchain protocols as well as the industrial organization of mainstream sectors with similar characteristics but ambiguous prior findings.

Manuel Schlegel, Liudmila Zavolokina, Gerhard Schwabe

The blockchain, the ledger that underlies the famous cryptocurrency Bitcoin, has huge implications for many industries. There have been various papers dedicated to research how blockchain technology will transform businesses and industries. However, current research lacks an overview of what the blockchain implies for the biggest stakeholder of these businesses and industries: consumers. This paper aims to provide an overview of how the blockchain affects consumers. We conduct a systematic literature review and enrich it with interview-based knowledge from blockchain experts to show how blockchain technology changes business sectors, name affected consumers in these sectors, derive implications for these consumers and list existing as well as currently emerging blockchain-based products and services. Finally, we warn of the technical, institutional and human challenges and manifold pitfalls blockchain technology must overcome to gain widespread adaptation among consumers.

Franciska Mifanyira, Sophia C. B. Kusumawardhani

No abstract is available for this record.

Jan-Philipp Arps

With the invention of the cryptocurrency Bitcoin in 2009, the world's first blockchain application was developed. While academic research gradually begins to investigate cryptocurrencies more closely and attempt to understand their functioning, technology is rapidly evolving and ecosystems grow exponentially. The research is still scattered and chaotic and has not produced common guidelines. Therefore, the question remains: how sustainable cryptocurrencies and their digital ecosystems are.Only a few models and frameworks take a holistic view on digital sustainability. Only two frameworks were identified that take distributed ledger technologies (blockchain) or cryptocurrencies into consideration: the three governance strategies for digital sustainability of Linkov et al. (2018) and 10 basic conditions of sustainable digital artifacts according to Stuermer, Abu-Tayeh and Myrach (2016). These two frameworks were combined into a new integrated sustainability framework for cryptocurrencies. The developed integrated sustainability framework consists of four dimensions and 12 categories.Existing secondary data, self-conducted social media interviews and practical insights gained through an ASIC mining experiment were used to fill the framework with sufficient data. It confirms Bitcoin's sustainability problems in energy consumption and scalability, highlights Ethereum's great potential as a blockchain platform and explains the higher scalability and faster payment of Ripple and IOTA.While 2017 marked the temporary peak of the cryptocurrency hype, 2018 was a transformative year in which the leading cryptocurrencies were increasingly occupying more specialised niches.

Usman Chohan

No abstract is available for this record.

Mads Frederik Madsen, Mikkel Gaub, Malthe Ettrup Kirkbro, Tróndur Høgnason · 6 authors

We study distributed declarative workflow execution in an adversarial setting.In this setting, parties to an agreed-upon workflow do not trust each other to follow that workflow, or suspect the other party might misrepresent proceedings at a later time.We demonstrate how distributed declarative workflow execution can be implemented as smart contracts, guaranteeing (I) enforcement of workflow semantics, and (II) an incontrovertible record of workflow execution history.Crucially, we achieve both properties without relying on a trusted third party.The implementation is based on the Ethereum blockchain, inheriting the security properties (I) and (II) from the guarantees given by that chain.A recurring challenge for both the implementation and the analysis is the cost of operations on Ethereum: This cost must be minimised for honest parties, and an adversary must be prevented from inflicting extra cost on others.

Filippo Boiani

Electronic Health Records (EHRs) are both crucial and sensitive as they contain essential information and are frequently shared among different parties including hospitals, pharmacies or private clinics. This information must remain correct, up to date, private, and accessible only to the authorized people. Moreover, the access must also be assured under special conditions mass crises like hurricanes or earthquakes where disruption, decentralized responses, and chaos could potentially lead to wrong procedures or even malicious behaviors. The introduction of blockchain a distributed ledger where the records are stored in a linked sequence of blocks and are theoretically difficult to delete or tamper with made possible to design and implement new solutions for more failure-resistant EHRs applications adopting a distributed and decentralized philosophy, in contrast with the central ones based on cloud infrastructures or even local solutions. In this context, this work provides a systematic study to understand whether permissioned blockchain implementations could be of any benefit to managing health records in emergency situations caused by natural disasters. After the design and implementation of a basic prototype for an EHRs management system in Hyperledger Fabric and the execution of a set of test cases based on the simulation of the Haiti earthquake of 2010, it was possible to discuss the benefits and tradeoffs that the system entails. The discussion focused on the performance parameters like throughput, latency, memory and CPU usage. The system allowed the patients and practitioners to share and access EHRs and be able to detect and react to the crisis situations. Moreover, it behaved correctly in the presence of malicious nodes assuring throughputs and latencies still lower, compared to current centralized systems like credit card payments, but already up to two orders of magnitude higher than permissionless blockchain implementations. Even though there is still a lot of work to do, the system represented by the prototype could be an interesting alternative for networks of healthcare companies to help ensuring the continuity of treatment while preserving privacy and confidentiality in extreme situations.

Bruno Biais, Christophe Bisière, Matthieu Bouvard, Catherine Casamatta

No abstract is available for this record.

Xiaohong Zhang, Mochan Fan

The smart terminal and grid protection devices play a very important role in the safe operation of the smart grid. Traditional maintenance and renewal of the center node wastes a lot of manpower and material resources and have huge safety implications. This paper proposes a safety equipment diagnosis mechanism based on consortium blockchain technology to realize more efficient, convenient, and secure device maintenance. When a device has problems or notices improper operation, it can make a device diagnosis request in the consortium blockchain network, and receive a diagnosis response from a vendor or non-original supplier nodes. This scheme designs a decentralized safety equipment diagnosis smart contract, combining response node bid price and credit, and applies a multi-dimensional reverse auction mechanism to determine bid node and transaction price. After a smart device diagnosed, the relevant message will be packaged and sent to a smartphone, which can use the client to set up the smart contract of equipment operation policy. Paillier encryption arithmetic can be used to ensure device diagnosis mechanism safety. The proposed scheme is guaranteed not to reveal sensitive information in the process of device interaction.

Jeffrey M. Lipshaw

“Smart contracts” are a hot topic. Presently, smart contracts are mostly evidence of property, like cryptocurrencies or mortgages, created and/or transferred using blockchain technology. This is an exploration of the theoretical possibilities of artificial intelligence in a far broader range of complex and heretofore negotiated transactions that occur over time. My goal is to understand what it means to make a contract smarter, i.e. to delegate more and more of the creation, performance, and disposition of legally binding transactions to machine thinking. Moreover, I want to do so from the perspective of one who is neither a true believer in the purported technological singularity to come nor a digital Luddite.

Jamil Civitarese

No abstract is available for this record.

Ikhlaas Gurrib

No abstract is available for this record.

Rebecca Webster

Although more common internationally, some US companies are paying their employees in cryptocurrencies such as Bitcoin either internally or using a third-party administrator such as Bitwage.Bitwage boasts two-

Stefan Seebacher, Maria Maleshkova

The concept of blockchain technology has gained significant momentum in practice and research in the past few years, as it provides an effective way for addressing the issues of anonymity and traceability in distributed scenarios with multiple parties, which have to exchange information and want to securely collaborate with each other. However, up-to-date, the impact of the structure and setup of business networks on successfully applying blockchain technology, remains largely unexplored. We propose a model-driven approach, combining an ontology and a layer model, that is capable of capturing the properties of existing blockchain-driven business networks. The layers are used to facilitate the comprehensive description of such networks. We also introduce the Blockchain Business Network Ontology (BBO), formalizing the concepts and properties for describing the integral parts of a blockchain network. We show the practical applicability of our work by evaluating and applying it to an available blockchain use case.

Imran Makhdoom, Mehran Abolhasan, Wei Ni

Copyright © 2018 by SCITEPRESS – Science and Technology Publications, Lda. All rights reserved Bitcoin has revolutionized the decentralized payment system by excluding the need for a trusted third party, reducing the transaction (TX) fee and time involved in TX confirmation as compared to a conventional banking system. The underlying technology of Bitcoin is Blockchain, which was initially designed for financial TXs only. However, due to its decentralized architecture, fault tolerance and cryptographic security benefits such as user anonymity, data integrity and authentication, researchers and security analysts around the world are focusing on the Blockchain to resolve security and privacy issues of IoT. But at the same time, default limitations of Blockchain, such as latency in transaction confirmation, scalability concerning Blockchain size and network expansion, lack of IoT-centric transaction validation rules, the absence of IoT-focused consensus protocols and insecure device integration are required to be addressed before it can be used securely and efficiently in an IoT environment. Therefore, in this paper we analyze some of the existing consensus protocols used in various Blockchain-based applications, with a focus on investigating significant limitations in TX (Transaction) validation and consensus mechanism that make them inappropriate to be implemented in Blockchain-based IoT systems. We also propose a way forward to address these issues.

Jonathan Chiu, Thorsten V. Koeppl

No abstract is available for this record.

António Brandão, Henrique São Mamede, Ramiro Gonçalves

No abstract is available for this record.

Mutugi Mutegi

No abstract is available for this record.

George Bouchagiar

Initial Coin Offering (ICO) has become global. Cryptocurrencies are offered to finance projects in the blockchain arena. This crypto-phenomenon challenges traditional capital raising and investment mechanisms and many strongly believe in its potential. This paper analyses some key characteristics of ICOs and investigates potential risks. It also examines the shift from traditional mechanisms to “cryptos” and studies several features of blockchains. An overview on trust is provided to detect some trust-enhancing and trust-diminishing aspects of technologies. Finally, cryptology is discussed to test cryptocurrencies’ potential as objects of trust.

Nataliya Krasnikova, Nataliia Stukalo, O. O. Balash

The article reveals a conceptual basis of the cryptocurrency functioning. The main types of cryptocurrencies are featured and analyzed as well as their general strengths and weaknesses. Based on the price dynamics correlation analysis of some cryptocurrency types, a general low level of dependence between digital assets is established. The main functions of the cryptocurrency are formulated in the form of transformed money functions. Also, additional functions of cryptocurrencies are defined on the basis of their innovative nature, as well as the role in the modern financial system and world economic relations.