This study examines the volatility of certain cryptocurrencies and how they are influenced by the three highest capitalization digital currencies, namely the Bitcoin, the Ethereum and the Ripple. We use daily data for the period 1 January 2018-16 September 2018, which represents the bearish market of cryptocurrencies. The impact of the decline of these three cryptocurrencies on the returns of the other virtual currencies is examined with models of the ARCH and GARCH family, as well as the DCC-GARCH. The main conclusion of the study is that the majority of cryptocurrencies are complementary with Bitcoin, Ethereum and Ripple and that no hedging abilities exist among principal digital currencies in distressed times.
In this paper, we introduce a machine learning predictive model that detects patterns of security vulnerabilities in smart contracts. We adapted two static code analyzers to label more than 1000 smart contracts that were verified and used on the Ethereum platform. Our model predicted a number of major software vulnerabilities with the average accuracy of 95 percent. The model currently supports smart contracts developed in Solidity, however, the approach described in this paper can be applied to other languages and blockchain platforms.
Emmanuelle Anceaume, Marina Papatriantafilou, Maria Potop-Butucaru, Philippas Tsigas
This paper continues the recent line of academic effort dedicated to formalizing distributed ledgers. This work is the first one to propose a specification of distributed ledger register that matches the Lamport hierarchy from safe to atomic. Moreover, we propose implementations of distributed ledger registers with safe, regular and atomic guaranties in a model of communication specific to distributed ledgers technology that we also formalize. Then, we propose an implementation of a distributed ledger register that satisfies the atomic specification and the k-consistency property that characterises the permissionless distributed blockchains such as Bitcoin and Ethereum.
Internet of Things (IoT) is growing at an exponential rate but the area of privacy and security in IoT still remains unexplored. The existing algorithms or methods are mainly centralized and hence they are vulnerable due to their single point authentication topology. As it has been estimated that by 2020 there will be more ‘things’ than people on this earth the problem of security becomes a major concern in IoT networks, as a person having control to an IoT network will be able to control a large portion of an organization. Blockchain has recently been used to provide security to peer-to-peer networks. Blockchains are computationally expensive, heavyweight and are considered unsuitable for IoT architecture. In this paper a new lightweight and secure architecture for IoT by using Ethereum Blockchain retaining most of its security providing powers is proposed. Since Blockchain is decentralized it solves the single point authentication problem existing in IoT networks. A Smart Home System as a representative case study has been implemented for broader IoT applications. The two parameters measured are temperature and intrusion detection. The proposed model tackles some more challenges that exist in IoT networks. The Qualitative evaluation of the proposed architecture highlights how it tackles various attacks.
The Blockchain for Education platform helps us to make the tamper-proof certificates and their correct and the overall permanent allocation of these certificates to learners, as well as verification of certificates. It can reduce the overall frauds and tampering of the degrees and certificates. Blockchain technology can be used to solve many educational problems and can help educators as well as learners to monitor the learning outcomes. The data can be stored securely and tamper proof format when it’s stored onto the blockchain network. Here smart contracts can be designed and deployed on to the Ethereum blockchain that can be designed using the solidity programming language. Blockchain can be applied to private, public and consortium sectors depending upon the usage and the scope of the blockchain. Education system can take benefit of this scalability of the blockchain and can be effectively useful in the educational institutions.
La tesi si e occupata di studiare le caratteristiche della tecnologia blockchain e di comprendere come queste siano state introdotte nell’industria dell’automotive e dei sistemi di mobilita. La blockchain e una tecnologia che negli ultimi anni e stata spesso al centro del dibattito scientifico e del mondo dell’industria. Questa tecnologia, sebbene non si sia ancora imposta come sostituta delle tecnologie tradizionali, e considerata come una risorsa rivoluzionaria che ha permesso di conoscere un nuovo modo di pensare lo scambio di informazioni e beni. Tra i diversi campi in cui la blockchain puo essere utilizzata come strumento su cui basare lo sviluppo di nuove applicazioni e di nuovi sistemi, e necessario menzionare l’industria dell’automotive ed i sistemi di mobilita. Tali settori, infatti, negli ultimi anni hanno avuto dei notevoli cambiamenti sia dal punto di vista tecnologico che nei principi dello sviluppo di nuove automobili e dei modi di intendere la mobilita. Si evince una propensione ad una nuova cultura dell’automobile, che cerca di realizzare e migliorare i veicoli, non solo dal punto di vista delle performance ma anche sotto gli aspetti dei consumi e dell’impatto ambientale. Questa evoluzione ha introdotto dei cambiamenti anche nel modo di pensare i sistemi di mobilita che, adesso, permettono alle persone di condividere viaggi, di utilizzare veicoli affittabili nelle citta e di pianificare e programmare i propri spostamenti in maniera veloce e intuitiva. Il lavoro di tesi e stato svolto in diverse fasi. Nella prima fase si e approfondito lo studio della blockchain, delle sue caratteristiche fondamentali e delle sue diverse implementazioni che possono essere differenti a seconda di diverse necessita progettuali. Nella seconda fase, si e effettuata una ricerca riguardo il coinvolgimento della blockchain nell’industria dell’automotive e della mobilita. Si sono cercati e catalogati i diversi settori, attraverso la ricerca di documenti, pubblicazioni e applicazioni, in cui venivano proposte soluzioni che prevedessero l’utilizzo della blockchain. Dopo questa fase di ricerca, il lavoro di tesi e proseguito con l’individuazione di un caso d’uso a partire dai risultati ottenuti dall’analisi dell’utilizzo della blockchain nell’industria dell’automotive e della mobilita. I risultati hanno determinato un forte interesse nel settore del trasporto multimodale che si occupa di combinare diverse tipologie di veicolo per effettuare singoli spostamenti. Si e indagato, quindi, sulla possibilita di realizzare una piattaforma di mobilita innovativa, basata sull’utilizzo della blockchain pubblica Ethereum, che permetta all’utente di acquistare, con un’unica operazione, un viaggio che sfrutti diversi tipi di veicoli e, di conseguenza, che coinvolga diversi fornitori di servizi di mobilita. Si e realizzata, quindi, l’architettura di tale piattaforma, definendo i diversi attori coinvolti, i dati e i beni scambiati tra gli attori, le modalita di comunicazione e le tecnologie utilizzate per lo scambio dei dati e beni. E' stato realizzato, infine, un proof-of-concept che fornisce un esempio applicativo dell’architettura stessa. A conclusione della tesi, viene evidenziato come la piattaforma sia in grado di fornire e combinare diversi tipi di veicoli per effettuare un viaggio, permettendo all’utente di poterlo pianificare, acquistare, gestire ed infine di pagare automaticamente i diversi servizi.
A cryptocurrency is a digital or virtual currency designed to work as a medium of exchange. It uses cryptography to secure and verify transactions as well as to control the creation of new units of a particular cryptocurrency. Essentially, cryptocurrencies are limited entries in a database that no one can change unless specific conditions are fulfilled. Here, in this chapter, the authors demystify Ethereum cryptocurrency. Initially, they introduce the said topic. While explaining, they follow a layered approach and explain each layer that is contributing in transactions. Eventually, they show the challenges for Ethereum cryptocurrency.
The Ethereum blockchain is essentially a globally replicated public database.\nPrograms called smart contracts can access this database. Over 10 million smart\ncontracts have been deployed on the Ethereum blockchain. Executing a method of\na smart contract generates a transaction that is also stored on the blockchain.\nThere are over 1 billion Ethereum transactions to date. Smart contracts that\nare transparent about their function are more successful than opaque contracts.\nWe have therefore developed a tool (ContractVis) to explore the transparency of\nsmart contracts. The tool generates a replay script for the historic\ntransactions of a smart contract. The script executes the transactions with the\nsame arguments as recorded on the blockchain, but in a minimal test\nenvironment. Running a replay script provides insights into the contract, and\ninsights into the blockchain explorer that was used to retrieve the contract\nand its history. We provide five concrete recommendations for blockchain\nexplorers like Etherscan to improve the transparency of smart contracts.\n
Open access
3 source records
Blockchain Technology Applications and Security
Auction Theory and Applications
Advanced Steganography and Watermarking Techniques
La blockchain ha sido conocida primero a través de uno de sus más atractivos desarrollos: las criptomonedas (Ver Código QR). Hoy, palabras como Bitcoin, Ethereum, Ripple, Litecoin son oídas a diario en los noticieros, portales, redes sociales, etc., pues las monedas digitales han establecido un paradigma para todo el sistema monetario. Hoy la gestión de la salud debe pensarse como una Smart Health Care (SHC). El aprovechamiento de las tecnologías debe trascender el ejercicio de la salud, desde la atención por parte del personal médico, la gestión de centros médicos, la comunicación paciente-médico, hasta la gestión del big data, resultado de las múltiples entradas de datos en el entorno de la salud.
Petar Kochovski, Sandi Gec, Vlado Stankovski, Marko Bajec · 5 authors
Trust is a crucial aspect when cyber-physical systems have to rely on resources and services under ownership of various entities, such as in the case of Edge, Fog and Cloud computing. The DECENTER’s Fog Computing Platform is developed to support Big Data pipelines, which start from the Internet of Things (IoT), such as cameras that provide video-streams for subsequent analysis. It is used to implement Artificial Intelligence (AI) algorithms across the Edge-Fog-Cloud computing continuum which provide benefits to applications, including high Quality of Service (QoS), improved privacy and security, lower operational costs and similar. In this article, we present a trust management architecture for DECENTER that relies on the use of blockchain-based Smart Contracts (SCs) and specifically designed trustless Smart Oracles. The architecture is implemented on Ethereum ledger (testnet) and three trust management scenarios are used for illustration. The scenarios (trust management for cameras, trusted data flow and QoS based computing node selection) are used to present the benefits of establishing trust relationships among entities, services and stakeholders of the platform.
In this paper, we propose a blockchain powered automated self-incited fire detection sensors connected to smart buildings.This solution is based on utilizing Ethereum smart contracts to coordinate and monitor the interaction between the
Ethereum is a type of cryptocurrency that exhibits an open-source, public, blockchain-based distributed computing platform and operating system featuring smart contract functionality. Ethereum is a cryptocurrency whose blockchain is generated by the Ethereum platform. Ethereum can be transferred between accounts and used to compensate participant mining nodes for computations performed. Ethereum attracts the attention of investors when the price of ether is increased sharply in the year of 2017. Therefore, the objective of this study is to forecast the value of the exchange rate of Ethereum using high-frequency data. The findings of this study will help investors to evaluate the appropriateness of Ethereum to be selected as one profile in the investment portfolio. This study developed the forecasting method using the autoregressive integrated moving average (ARIMA). The forecasting model investigated in this study is ARIMA (1,1,1) and ARIMA(1,1,2). ARIMA (1,1,2) shows a higher value of R-squared and lower the value of Akaike info criterion. Therefore, ARIMA(1,1,2) is a better model to estimate the likelihood of a model to estimate the future values of the Ethereum exchange rate. The ex-ante forecasting calculation indicates the mean absolute percentage error is 0.54 percentages. Therefore, the ARIMA (1,1,2) is a reliable model for forecasting. In conclusion, the Ethereum exchange rate can be forecast using high-frequency data with the implementation of reliable ARIMA model namely ARIMA (1,1,2).
The Internet of things (IoT) presents new opportunities and challenges due to its scale and dynamic nature. One significant challenge for the IoT is the need for security, in particular access control solutions, that are designed to meet the characteristics of these systems. Delegation of rights, from one entity to another, is a crucial component of an access control system. The IoT requires a secure, flexible, and fine-grained delegation model. While there has been considerable work in the area of delegation, much of it assumes a centralized, well-resourced system and these solutions have limited capacity in the context of the IoT. Where delegation models for the IoT have been proposed they typically provide only coarse-grained control over the delegation of rights. Moreover, many of them require a centralized trusted authority, which can suffer from a single-point failure and is not an ideal base for a large and dynamic system like the IoT. In this paper, we propose an identity-less, asynchronous, and decentralized delegation model for the IoT based on blockchain technology. We describe system components, architecture, and key aspects related to the security of the system. We use attributes to validate an entity rather than depending upon unique identities. We demonstrate the feasibility of our model through use-case examples and analyze the performance with a proof of concept testbed implementation using Ethereum private blockchain.
We study the time varying co-movement patterns of the crypto-currency prices with the help of wavelet-based methods; employing daily bilateral exchange rate of four major crypto-currencies namely Bitcoin, Ethereum, Lite and Dashcoin. First, we identify Bitcoin as potential market leader using Wavelet multiple correlation and Cross correlation. Further, Wavelet Local Multiple Correlation for the given crypto-currency prices are estimated across different time-scales. From the results, it is found that that the correlation follows an aperiodic cyclical nature, and the crypto-currency prices are driven by Bitcoin price movements. Based on the results obtained, we suggest that constructing a portfolio based on crypto-currencies may be risky at this point of time as the other crypto-currency prices are mainly driven by Bitcoin prices, and any shocks in the latter is immediately transformed to the former.
Oliver James Scholten, David Zendle, James Alfred Walker
This paper describes the York Combined Transaction Set (YCTS), which offers a single consolidated list of publicly available gambling related transactions derived from the Ethereum blockchain. This data includes over 1.4M individual transactions across 17,000+ unique addresses, which represent spending on decentralised gambling smart contracts. These contracts, and corresponding applications, have been selected based on their popularity as presented by an officially recognised ranking service, and have transacted over £240M by naive estimation over the past 10 months. Given the historical opacity of data driven gambling research, our contribution is to identify, and make available in a simple form, the transaction data found on the Ethereum blockchain such that existing questions surrounding player spending can be explored, and differences between decentralised and traditional forms of gambling can be identified.
Weiqi Dai, Chunkai Dai, Kim‐Kwang Raymond Choo, Changze Cui · 6 authors
Data, a key asset in our data-driven economy, has fueled the emergence of a new data trading industry. However, there are a number of limitations in conventional data trading platforms due to the existence of dishonest buyer/data broker. To mitigate these limitations, we posit the importance of a data processing-as-a-service model, which complements the conventional data hosting/exchange-as-a-service model. Specifically, in this paper, we introduce a secure data trading ecosystem and present a new blockchain-based data trading ecosystem (hereafter referred to as SDTE). In the ecosystem, both data broker and buyer are not able to obtain access to the seller's raw data, as they are only getting access to the analysis findings that they require. In other words, we reduce the challenge of securing the dataset to the challenge to secure the data processing. We also build a security model to analyze the data trading market and describe a new set of trading protocols for the entire data trading market. To demonstrate utility, we implement our proposed secure data trading platform (SDTP) on Ethereum & Intel's Software Guard Extensions (SGX) and perform an in-depth analysis.
Sustav za nagrađivanje korisnika koji dijele podatke namijenjen je demonstraciji Plasme kao jednog od predloženih rješenja za skaliranje platforme Ethereum. Plasma je skup pravila i najboljih praksi koje određuju način na koji se povezuju podlanci s glavnom lancem sustava Ethereum. Glavni lanac, u ovom slučaju, preuzima ulogu suca u svim sporovima koji se događaju na Plasma podlancu. Sustav za nagrađivanje odabran je kao primjer zato što generira vrlo veliku količinu transakcija u produkcijskoj okolini. U stvarnom svijetu, podatci generirani s korisničkih senzora stvorili bi konstantan tok podataka koji bi morao biti obrađen na pametnom ugovoru - aplikaciji koja se izvodi u raspodijeljenoj okolini sustava Ethereum. S obzirom na probleme propusnosti transakcija s kojima se sustav susreće, potrebno je rješenje koje će uvelike povećati kapacitet sustava u smislu količine obradivih transakcija u sekundi. Oslanjajući se na prakse definirane Plasma pravilima, sustav za nagrađivanje razvijen na podlancu omogućuje upravo to. Korisnicima je omogućeno konstantno dijeljenje podataka, za koje su nagrađeni od strane sustava koji validaciju vrši putem pametnog ugovora objavljenog na podlancu. Kako bi korisnici imali koristi od nagradnih tokena koje im dodijeli sustav, omogućeno im je sigurno i jednostavno prebacivanje sredstava s Plasma podlanca na glavni lanac sustava Ethereum. U okviru ovog rada je razvijen sustav u raspodijeljenoj okolini, s visokom propusnošću transakcija i visokom razinom sigurnosti koji garantira platforma Ethereum.