Summary In this paper, we analyze the Ethereum blockchain using the complex networks modeling framework. Accounts acting on the blockchain are represented as nodes, while the interactions among these accounts, recorded on the blockchain, are treated as links in the network. Using this representation, it is possible to derive interesting mathematical characteristics that improve the understanding of the actual interactions happening in the blockchain. Not only, by looking at the history of the blockchain, it is possible to verify if radical changes in the blockchain evolution happened.
This paper investigates the level of liquidity of digital currencies during the very intense bearish phase in their markets. The data employed span the period from April 2018 until January 2019, which is the second phase of bearish times with almost constant decreases. The Amihud’s illiquidity ratio is employed in order to measure the liquidity of these digital assets. Findings indicate that the most popular cryptocurrencies exhibit higher levels of liquidity during stressed periods. Thereby, it is revealed that investors’ preferences for trading during highly risky times are favorable for well-known virtual currencies in the detriment of less-known ones. This enhances findings of relevant literature about strong and persistent positive or negative herding behavior of investors based on Bitcoin, Ethereum and highly-capitalized cryptocurrencies in general. Notably though, a tendency towards investing in the TrueUSD stablecoin has also emerged.
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. 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. 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
Pendidikan kewarganegaraan membahas mengenai globalisasi dimana dengan adanya materi tentang globalisasi diharapkan menambah kecerdasan warga negara (civic intelligence) sehingga diharapkan kemampuan warga negara (civic skills) akan meningkat sehingga mampu menyikapi perubahan zaman dengan lebih bijak terutama perubahan yang diakibatkan dari globalisasi itu sendiri. Dampak globalisasi yang paling nyata adalah perkembangan IPTEK terutama perkembangan teknologi dan internet yang semakin pesat. Globalisasi dan Internet membawa perubahan baru salah satunya adalah Revolusi Industri 4.0 dimana Revolusi Industri 4.0 didukung oleh otomatisasi, digitalisasi, dan internet koneksi dari berbagai peralatan yang digunakan manusia dan salah-satu produk dari digitalisasi adalah munculnya istilah aset digital dimana aset digital adalah data yang ada dalam bentuk file biner, aset ini dapat dilihat sebagai barang nyata yang sering di klaim kepemilikan dan kontrol atas nilainya dimana salah-satu contoh aset digital yang ada di tengah masyarakat adalah kripto aset dimana aset digital yang berbentuk kripto aset ini dapat diperjual-belikan melalui suatu bursa aset digital yang harganya ditentukan murni atas permintaan dan penawaran dan dengan dapat diperdagangkannya aset digital ini maka menimbulkan hak-hak serta kewajiban baik dari pihak pedagang maupun dari pihak konsumen sehingga perlu adanya suatu perlindungan bagi kosumen yang melakukan transaksi aset digital (Bitcoin, Ethereum, Dash, dll) di Indonesia. Secara normatif ruh perlindungan konsumen di Indonesia ada pada UndangUndang Republik Indonesia Nomor 8 Tahun 1999 Tentang Perlindungan Konsumen yang hingga kini belum direvisi sehingga dipertanyakan peran serta keefektifitasannya dalam memberikan perlindungan terhadap konsumen khususnya konsumen yang melakukan transaksi aset digital (Bitcoin, Ethereum, Dash, dll) di Indonesia.
Civic education discusses globalization where the existence of material about globalization is expected to increase the intelligence of citizens and expected citizens' abilities will increase and they are able to respond to changes in the times more wisely, especially changes resulting from globalization itself. The most obvious impact of globalization is the development of science and technology, especially the rapid development of technology and the internet. Globalization and the Internet bring new changes, one of which is the Industrial Revolution 4.0, where the Industrial Revolution 4.0 was supported by automation, digitalization, and internet connections from various equipment used by humans and one of the products of digitalization is the emergence of the term digital assets where digital assets are data in the form of binary files, these assets can be seen as tangible goods that are often claimed ownership and control over their value. The example of digital assets that exist in the community is crypto assets where crypto-shaped digital assets can be traded through a digital asset exchanges whose prices are determined purely on demand and supply and because digital assets being able to trade these digital assets give rise to rights and obligations of both the merchant and the consumer so there is a need for protection for consumers who conduct digital asset transactions (Bitcoin, Ethereum, Dash, etc.) in Indonesia. Normatively the spirit of consumer protection in Indonesia is in the Republic of Indonesia Law Number 8 of 1999 concerning Consumer Protection, which until now has not been revised so that its effectiveness and role in providing protection to consumers are particularly questionable for consumers who conduct digital asset transactions (Bitcoin, Ethereum, Dash, etc.) in Indonesia.
Purpose This study aims to examine the properties of four major cryptocurrencies and how they can be used as a simpler alternative mode of hedging foreign exchange (FX) risks as compared to existing mainstream financial risk management techniques. Design/methodology/approach This study uses a combination of visual data representations and the classic Fama and Macbeth (1973) two-pass procedure regressions. Findings The findings show that cryptocurrencies can be a more effective hedge against FX risks as compared to other common hedging instruments and/or techniques such as gold or a diversified currency portfolio. Research limitations/implications The conclusions were arrived at based only on a small group of cryptocurrency, i.e. Bitcoin, Ethereum, Litecoin and Ripple. Other cryptocurrencies such as Dogecoin or ZCash might exhibit different properties. Practical implications Cryptocurrencies can be cost-effective and cost-efficient instruments that provide a solid hedge for investors and/or firms that are exposed to global FX volatility. Its ease of trade and virtually zero barriers to entry makes it an easily accessible alternative hedge instrument as compared to more complex items such as derivatives. Originality/value If cryptocurrencies are to be accepted into mainstream usage, a detailed examination of its various uses is necessary. In particular, as they are often touted to be the future of currency, its properties and price behavior relative to other mainstream financial instruments need to be well-understood, not only by finance professionals but also by laypersons.
This chapter looks at the whole landscape involving initial coin offerings (ICOs) beginning with their history, how they came into being, selling of pre-mined tokens, the advantage and disadvantages of investing through ICOs, and issues related to regulation and scams surrounding this new crowdfunding approach. The primary objective of investors to buy tokens through ICOs is to invest money on the potential of a future product. The purpose of arranging an ICO is to raise money for a future project selling its pre-mined tokens to investors. The success of the Ethereum ICO made it possible to generate funds from the initial coin offerings for the development of blockchain projects by releasing some or all of the native tokens. According to the ICO Watch List, the network and telecommunication industry attracted the most significant sum raised by ICOs. The successful launch of the Ethereum platform encouraged other projects to raise capital using ICOs.
Blockchain is a digital tracker that maintains instant and permanent records validated across a specific chain of computers. This process makes it easy to spot fraudulent behavior, making the transaction more secure. Hence it is very much important to ex plore on such emerging technologies which will be essential for applications such as Smart Property, Smart Contracts, Internet of Things, Financial Services etc. At- tacks like Distributed Denial-of-Service (DDoS) pose a growing threat to computer networks and internet services. Existing strategies for mitigating DDoS attacks are inecient because of lacking resources and inexibility. Blockchains like Ethereum enable new ways to prevent against DDoS attacks: Using smart contracts, IP addresses of attackers can be signalized without additional infrastructure. The exponential increase of traffic volume makes DDoS attacks a top security threat to service providers and addressing this is the crux of Blockchain Technology. Bitcoin has been the most popular cryptographic currency since it was invented and it is the best example that uses the Blockchain technology. To avoid an attack, the network uses the Blockchain consensus which addresses various algorithms such as Proof-of-Work(PoW), Proof-of-Stake(PoS) etc. This seminar work focuses on studying how Blockchain can be used as a Security Mechanism to prevent Ddos Attacks which may also provide insights for implementation of certain applications.
This chapter explains the opportunity to present some of the platforms that have earned a reputation from both industry and academia. It discusses some emerging blockchains that have the potential to disrupt the industry in the future. Existing public ledgers such as Bitcoin and Ethereum are not fast enough to provide adequate support to applications that require a response in the fraction of a second. IOTA is a distributed ledger designed for the Internet of Things (IoT). It provides secure communications and payments between IoT devices and will soon have a smart contract service called Qubic. Hyperledger is a collaborative attempt between IBM and Linux Foundation to build an enterprise-grade, open-source distributed ledger framework. The Indy platform supports independent identities on distributed ledgers and provides the necessary tools, libraries and reusable components for implementing digital identities rooted on blockchains or other distributed ledgers.
This chapter aims to introduce smart contracts, and describes how Ethereum stands out from Bitcoin and opens a new world for the development of distributed applications. Ethereum extends the concept of blockchain one step further, and instead of only validating, storing, and replicating transaction data, it also allows users to write and run computer programs. Ethereum has a metric system of denominations used as units of Ether. The primary motivation of designing Ethereum was to extend the capabilities of Bitcoin, therefore, it incorporates many features and technologies that its predecessor utilised. The Ethereum blockchain did not follow that footstep; it instead ties up all exchanges with the account to recognise the transfers of value and information. The Ethereum platform defines every account by a pair of keys: a private key and a public key, where the latter is used to generate the address of the account.
Internet of things (IoT) is becoming increasingly important and ubiquitous in home and industries. It makes object a part of the Internet and fuses the digital and physical world together. However, if not properly secured, IoT device can be vulnerable to tampering that can change the content of the data stored in the network. Blockchain, a technology used in cryptocurrency, can be used for addressing the security and privacy challenges in IoT. Blockchain can be beneficial to IoT by adding more security layer and reducing dependency on a central authority. This paper proposed to develop a blockchain based platform for IoT application. Blockchain technology can be utilized to provide a decentralized network, creating a more secured IoT system. The proposed blockchain network will be based on Ethereum blockchain network allowing the use smart contract application for management of IoT devices. Experiment is conducted to show the feasibility of the blockchain based platform. The proposed blockchain based platform is capable of managing several IoT devices connected to the network.
Open access
Blockchain Technology Applications and Security
IoT and Edge/Fog Computing
Advanced Steganography and Watermarking Techniques
Cryptocurrency investigations have centered almost entirely around the transfer of value “money” or a cryptocurrency asset. The use of cryptocurrency for illicit purposes, especially Bitcoin, is well documented both in academic writing, media reporting and even film documentaries. The infamous SilkRoad market place in addition to the millions of dollars spent within dark markets on drugs, guns and assassinations have grabbed the headlines. This paper looks at how blockchain is creating new areas of investigation that are yet to be explored in detail. This scenario-based research examines the hosting of stolen data (P.I.I) personal identifiable information on a distributed blockchain host where the data is also accessible. The platform used is based on Ethereum infrastructure but demonstrates just one available platform that poses the paradigm. The paper examines the considerations through the lens of an incident responder /cyber investigator, forensics examiner and data controller. The scenario highlights distinct differences in considerations from a traditional response compared to dealing with the immutable and unstoppable distributed technology. The paper concludes that more is needed to be done to understand digital forensics in the blockchain era and the need to develop beyond track and trace in the cryptocurrency investigative tool box. The discussion also brings forth how data retention and GDPR requires consideration when applying it blockchain systems.
Stefano Angieri, Alberto García-Martínez, Bingyang Liu, Zhiwei Yan · 6 authors
The current system to manage the global pool of IP addresses is centralized in five transnational organizations, known as regional internet registries (RIRs). Each of them manages the address pool for many countries. In this paper, we present InBlock, a distributed autonomous organization that provides the decentralized management of IP addresses. The InBlock also fulfills the same objectives as those fulfilled by the current IP address allocation organizations, i.e., uniqueness, fairness, conservation, aggregation, registration, and minimized overhead. The InBlock is implemented as a set of blockchain's smart contracts in Ethereum, and it implements all the functions needed for the management of a global pool of addresses without any human intervention. Any entity may request an allocation of addresses to the InBlock registry by performing a (crypto)currency transfer to the InBlock. The fee required, along with the annual renewal fee, serves as a mechanism to deter stockpiling and other wasteful practices. As with any novel technology, there are many open questions about the usage of blockchains to build an IP address registry. For this reason, we believe that practical experimentation is required in order to have hands-on experience, so we propose to conduct an experiment on the InBlock as a starting point to inform about the future directions in this space.
Huashan Chen, Marcus Pendleton, Laurent Njilla, Shouhuai Xu
The blockchain technology is believed by many to be a game changer in many application domains, especially financial applications. While the first generation of blockchain technology (i.e., Blockchain 1.0) is almost exclusively used for cryptocurrency purposes, the second generation (i.e., Blockchain 2.0), as represented by Ethereum, is an open and decentralized platform enabling a new paradigm of computing --- Decentralized Applications (DApps) running on top of blockchains. The rich applications and semantics of DApps inevitably introduce many security vulnerabilities, which have no counterparts in pure cryptocurrency systems like Bitcoin. Since Ethereum is a new, yet complex, system, it is imperative to have a systematic and comprehensive understanding on its security from a holistic perspective, which is unavailable. To the best of our knowledge, the present survey, which can also be used as a tutorial, fills this void. In particular, we systematize three aspects of Ethereum systems security: vulnerabilities, attacks, and defenses. We draw insights into, among other things, vulnerability root causes, attack consequences, and defense capabilities, which shed light on future research directions.
Bitcoin and Ethereum, whose miners arguably collectively comprise the most powerful computational resource in the history of mankind, offer no more power for processing and verifying transactions than a typical smart phone. The system described herein bypasses this bottleneck and brings scalable computation to Ethereum. Our new system consists of a financial incentive layer atop a dispute resolution layer where the latter takes form of a versatile "verification game." In addition to secure outsourced computation, immediate applications include decentralized mining pools whose operator is an Ethereum smart contract, a cryptocurrency with scalable transaction throughput, and a trustless means for transferring currency between disjoint cryptocurrency systems.
Jason Teutsch, Vitalik Buterin, Christopher L. Brown
Ethereum has emerged as a dynamic platform for exchanging cryptocurrency tokens. While token crowdsales cannot simultaneously guarantee buyers both certainty of valuation and certainty of participation, we show that if each token buyer specifies a desired purchase quantity at each valuation then everyone can successfully participate. Our implementation introduces smart contract techniques which recruit outside participants in order to circumvent computational complexity barriers.
In December 2015, a bounty emerged to establish both reliable communication and secure transfer of value between the Dogecoin and Ethereum blockchains. This prized "Dogethereum bridge" would allow parties to "lock" a DOGE coin on Dogecoin and in exchange receive a newly minted WOW token in Ethereum. Any subsequent owner of the WOW token could burn it and, in exchange, earn the right to "unlock" a DOGE on Dogecoin. We describe an efficient, trustless, and retrofitting Dogethereum construction which requires no fork but rather employs economic collateral to achieve a "lock" operation in Dogecoin. The protocol relies on bulletproofs, Truebit, and parametrized tokens to efficiently and trustlessly relay events from the "true" Dogecoin blockchain into Ethereum. The present construction not only enables cross-platform exchange but also allows Ethereum smart contracts to trustlessly access Dogecoin. A similar technique adds Ethereum-based smart contracts to Bitcoin and Bitcoin data to Ethereum smart contracts.
Smart contract is a special program that manages digital assets on blockchain. It is difficult to recover the loss if users make transactions through buggy smart contracts, which cannot be directly fixed. Hence, it is important to ensure the correctness of smart contracts before deploying them. This paper proposes a systematic framework to mutation testing for smart contracts on Ethereum, which is currently the most popular open blockchain for deploying and running smart contracts. Fifteen novel mutation operators have been designed for Ethereum Smart Contracts (ESC), in terms of keyword, global variable/function, variable unit, and error handling. An empirical study on 26 smart contracts in four Ethereum DApps has been conducted to evaluate the effectiveness of mutation testing. The experimental results show that our approach can outperform the coverage-based approach on defect detection rate (96.01% vs. 55.68%). The ESC mutation operators are effective to reveal real defects and we found 117 out of 729 real bug reports are related to our operators. These show the great potential of using mutation testing for quality assurance of ESC.
Ethereum Virtual Machine (EVM) is the run-time environment for smart contracts and its vulnerabilities may lead to serious problems to the Ethereum ecology. With lots of techniques being continuously developed for the validation of smart contracts, the testing of EVM remains challenging because of the special test input format and the absence of oracles. In this paper, we propose EVMFuzzer, the first tool that uses differential fuzzing technique to detect vulnerabilities of EVM. The core idea is to continuously generate seed contracts and feed them to the target EVM and the benchmark EVMs, so as to find as many inconsistencies among execution results as possible, eventually discover vulnerabilities with output cross-referencing. Given a target EVM and its APIs, EVMFuzzer generates seed contracts via a set of predefined mutators, and then employs dynamic priority scheduling algorithm to guide seed contracts selection and maximize the inconsistency. Finally, EVMFuzzer leverages benchmark EVMs as cross-referencing oracles to avoid manual checking. With EVMFuzzer, we have found several previously unknown security bugs in four widely used EVMs, and 5 of which had been included in Common Vulnerabilities and Exposures (CVE) IDs in U.S. National Vulnerability Database. The video is presented at https://youtu.be/9Lejgf2GSOk.
While Ethereum run in public networks which make the blockchain size large and transaction run time longer than time for private or national network, that led to continuous worries over the expanding size of Ethereum Blockchain, which certainly reduce Cryptocurrency's effectiveness. The estimations were on increase and believed it would cross the node limit of 1 TB terribly shortly. If new consumer a full node enters to that blockchain and cryptocurrency world, a node is a computer software cum database of the blockchain, which a full node client must download on their personal computers to become a full node in the blockchain. in this way, the client can be verifying transaction on the network with the help of other nodes on the system. We proposed to implement national cryptocurrency which developed using Ethereum as a development platform that could serve national or regional people that has limited or slow internet connections like Iraq, in addition payments in countries with unstable fiat currencies, although cryptocurrencies are suffering from unstable exchange rates against fiat currencies, the use of national cryptocurrency instead of the native fiat cash could even be a far better alternative for individuals in certain countries like Iraq, Iran and Syria, with high rate of inflation. The reminder of this paper is arranging as following: an introduction, the advantages and drawbacks of cryptocurrencies, Background on Blockchain and Ethereum, implementation, results and conclusion.
Francesco Buccafurri, Vincenzo De Angelis, Gianluca Lax, Lorenzo Musarella · 5 authors
The main benefit of smart contracts over Ethereum is that different parties with conflicting interests can exchange value without trusting each other. As a matter of fact, solutions in which service delivery is regulated by smart contracts are proliferating. Sometimes, services can be negotiated and delivered only on the basis of some attributes, without disclosing the identity of the customer to the service supplier. However, accountability is still required, so that, in case of need, the identity of the customer should be linked to the service delivered and communicated to the appropriate parties. In this paper, we propose a practical solution to the above problem that integrates the features of Ethereum with a (Ciphertext-Policy) Attribute-Based Encryption scheme. To show the effectiveness of our proposal, we instantiate the general model to a significant use case.
Exploring dependence structures between financial time series has been important within a wide range of applications. The main aim of this paper is to examine dependence relationships among five well-known cryptocurrencies—Bitcoin, Ethereum, Litecoin, Ripple, and Stella—by a copula directional dependence (CDD). By employing a neural network autoregression model to avoid the serial dependence in each individual cryptocurrency, we generate residuals of the fitted models with time series of daily log-returns in percentage of the five cryptocurrencies and then we apply a Gaussian copula marginal beta regression model to the residuals to explore the CDD. The results show that the CDD from Bitcoin to Litecoin is highest among all ordered directional dependencies and the CDDs from Ethereum to the other four cryptocurrencies are relatively higher than the CDDs to Ethereum from those cryptocurrencies. This finding implies that the return shocks of Bitcoin have the most effect on Litecoin and the return shocks of Ethereum relatively influence the shocks on the other four cryptocurrencies instead of being affected by them. This allows investors to build the market-timing strategies by observing the directional flow of return shocks among cryptocurrencies.