At the beginning of 2020, the panic of Covid-19 had an excessive impact on global economics and the financial market. Based on the unit root test, this paper exposes the newly global Covid-19 confirmed cases and the rate of return of Ethereum and Bitcoin are stationary time series. This paper further completes the VAR model and ARMA-GARCH model. The VAR model examines the effect of newly confirmed cases on to rate of return of Bitcoin and Ethereum, and the ARMA-GARCH model scrutinizes the newly confirmed cases to the fluctuation of Bitcoin and Ethereum. This study found that the impact of the COVID-19 on cryptocurrency earnings was short-term, and did not improve the market volatility.
Tommaso Frassetto, Patrick Jauernig, David Koisser, David Kretzler · 7 authors
Smart contracts enable users to execute payments depending on complex program logic. Ethereum is the most notable example of a blockchain that supports smart contracts leveraged for countless applications including games, auctions and financial products. Unfortunately, the traditional method of running contract code on-chain is very expensive, for instance, on the Ethereum platform, fees have dramatically increased, rendering the system unsuitable for complex applications. A prominent solution to address this problem is to execute code off-chain and only use the blockchain as a trust anchor. While there has been significant progress in developing off-chain systems over the last years, current off-chain solutions suffer from various drawbacks including costly blockchain interactions, lack of data privacy, huge capital costs from locked collateral, or supporting only a restricted set of applications. \n \nIn this paper, we present POSE—a practical off-chain protocol for smart contracts that addresses the aforementioned shortcomings of existing solutions. POSE leverages a pool of Trusted Execution Environments (TEEs) to execute the computation efficiently and to swiftly recover from accidental or malicious failures. We show that POSE provides strong security guarantees even if a large subset of parties is corrupted. We evaluate our proof-of-concept implementation with respect to its efficiency and effectiveness.
Drone-based systems supporting Search and Rescue (SAR) missions help expeditiously improve the possibility of discovering the missing victims. Nonetheless, the current drone-based systems have some limitations, such as the need for humans in control of large-scale drones, drone’s energy inefficiency, repercussion of quality of service (QoS) from abnormalities events, shortages of automaticity and real-time interactions, deficiency of swift decisions from artificial intelligence-based SAR, and underestimation of security issues in SAR systems. Therefore, developing a more advanced drone-based system is necessary to overcome these limitations. However, it is challenging to achieve the target due to trade-off relationships of technologies and strict requirements of time-critical SAR. This paper studies the feasibility of an Internet-of-Drones (IoD) system using blockchain and artificial intelligence at the edge to overcome limitations and improve SAR QoS. An advanced IoD system architecture from drones to a back-end system and end-users terminals has been proposed. Furthermore, advanced edge services and artificial intelligence at the edge have been presented for automatically searching for missing persons. In addition, computation offloading approaches have been provided to improve the energy efficiency of drones and reduce system latency. Last but not least, public and private blockchain, including Ethereum and Hyperledger Fabric, for providing secure and decentralized healthcare platform has been investigated and analyzed to enable real-time interaction between healthcare entities and improves healthcare services. The results show that the proposed system helps overcome the limitations and improve the SAR QoS. Besides, the proposed system satisfies the security requirements, including confidentiality, integrity, authentication, authorization, access control, privacy, trust, transparency, availability, automaticity, and tolerance.
Despite the rapid growth of developing markets, aided by globalization, comparative studies of cryptocurrency and stock market volatility have focused on the developed markets and neglected developing ones. In this regard, this study compares cryptocurrency volatility with that of the Johannesburg Stock Exchange (JSE), a developing market. GARCH-type models are applied to daily log returns of Bitcoin, Ethereum, and the FTSE/JSE 4O in two ways. Firstly, the models are applied directly; secondly, structural breaks are tested and accounted for in the models. The sample period was from September 18, 2017, to May 27, 2021. The results show higher volatility and higher volatility persistence in cryptocurrency than in the JSE market. They also show that persistence is overestimated for cryptocurrencies when structural breaks are not accounted for. The opposite was true for the JSE.Moreover, the two cryptocurrencies were found to have close to identical volatility plots that differ from that of the JSE. High volatility periods of cryptocurrency also did not coincide with that of JSE and those of JSE did not coincide with the cryptocurrency ones. There is also evidence of an inverse leverage effect in cryptocurrency, which opposes the normal leverage effect of the JSE market.
Among the new way of exchanging money, using crypto currency has been very popular. Its also an investment to get good returns over the period of time. Cryptocurrency has grown to more than 120 million investors around the world as per a survey of 2021.Its growing at the 15 to 20% ratio around the world every year. This fact leads to a serious consideration of security and its vulnerabilities in block chain. Apart from market risks, high volatility, lack of rules and regulations, cyber risks are one of the most required types which needs proper attention and technical understanding. Because the crypto currencies are fully decentralized the risk of attacks is exposed and in most of the cases defenseless. Proof of stake and proof of work are two major algorithms followed by almost all crypto currencies to allot stocks to the holders. In this paper, different types of risks and attacks with POS and POW are explained with its mitigation. The problems and outcomes are examined, reviewed and conferred in case of Ethereum and Bitcoin crypto currencies. These currencies decentralized frameworks and anonymity attracts unlawful activities. Recognizing and preventing them needs understanding of the mechanism of attacks which are discussed in easiest possible ways for even a new-bee or an outsider person.
The enormous rise of the cryptocurrencies over the last few years has created one of the largest unregulated markets in the world. In this study, we obtain millisecond data for the five major cryptocurrencies—bitcoin, ethereum, ripple, litecoin and dash—and two cryptocurrency indices—Crypto Index (CRIX) and CCI30 Crypto Currencies Index—to investigate the relationship between cryptocurrency liquidity, herding behaviour and profitability during periods of extreme price movements (EPMs). We demonstrate that cryptocurrency traders (CTs) facilitate EPMs and demand liquidity even during the utmost EPMs. We observe the presence of herding behaviour during up markets across the entire dataset. Our robustness checks indicate that herding behaviour follows a dynamic pattern that varies over time with decreasing magnitude. We also provide novel evidence of CTs’ profitability after transaction costs, and demonstrate their strong profitability-generating record in the future.
Cryptocurrency is fastly gaining interest among Investors in India. In the past few years, there was a tremendous change in the number of investors and analysts suggest that cryptocurrency is not only for city slickers but also for small towns. Many of the investors of Cryptocurrency are from small towns and villages in India. This may prove that the cryptocurrency may serve as another medium of exchange and also another way of storing valuable metals etc as a property. This paper estimates the different types of Crypto Currency of BitCoin and Ethereum through different type of Analytical tools like Time Series Analysis ,ANOVA ,Correlation and Decision tree analysis and suggest for better investment strategies.
U ovom radu pratimo položaj umetnosti, umetnika i umetničkog dela s obzirom na uslove u kojima umetničko delo nastaje, u okruženju u kome vladaju kapital odnosi i visoko tehnološko okruženje koje ih prati. Prelaskom sa analognih na digitalne formate otvorene su nove perspektive za umetničko stvaralaštvo i distribuciju umetničkog dela, ali i probleme vezane za zaštitu autorskih prava i pravične monetizacije umetničkog dela. Pojavom blockchain tehnologije, posebno Ethereum blockchain platforme sa tehnologijom otvorenog koda i pametnim ugovorima omogućena je efikasnija komunikacija, distribucija i monetizacija umetničkog dela. Fokus ovoga rada posebno sužavamo na pojavu NFT nerazmenljivih tokena (Non Fungible Tokens) koji mogu biti nosioci vrednosti umetničkog dela. Oni omogućavaju da se održi unikatnost dela kroz kontrolisanu oskudicu. Predstavićemo standard ERC-721 koji omogućava kreiranje NFT-a, kao i prvih pet vodećih platformi za plasman NFT tokena na blokčejnu kroz odabrane primere.
Abu Kowshir Bitto, Imran Mahmud, Md. Hasan Imam Bijoy, Fatema Tuj Jannat · 7 authors
<span>Cryptocurrencies are encrypted digital or virtual money used to avoid counterfeiting and double spending. The scope of this study is to evaluate cryptocurrencies and forecast their price in the context of the currency rate trends. A public survey was conducted to determine which cryptocurrency is the most well-known among Bangladeshi people. According to the survey respondents, Bitcoin is the most famous cryptocurrency among the eight digital currencies. After that, we'll explore the four most well-known cryptocurrencies: Bitcoin, Ethereum, Litecoin, and Tether token. The 'YFinance' python package collects our cryptocurrency dataset, and the relative strength index (RSI) is employed to investigate these cryptocurrencies. Autoregressive (AR), moving average (MA), and autoregressive moving average (ARMA) models are applied to our time-series data from 2015-1-1 to 2021-6-1. Using the 'closing' price and a simple moving average (SMA) graph, bitcoin and tether are identified as oversold or overbought cryptocurrencies. We employ the seasonal decomposed technique into the dataset before implementing the model, and the augmented dickey-fuller test (ADF) indicates too much seasonality in the dataset. The autoregressive (AR) model is the most accurate in predicting the price of Bitcoin, Ethereum, Litecoin, and Tether-token, with 97.21%, 96.04%, 95.8%, and 99.91% accuracy, consecutively.</span>
Vikas Goel, Mukul Aggarwal, Amit Gupta, Narendra Kumar
An Aadhaar is a unique number issued to every citizen in India. Aadhar’s current identity authentication relies on the central identities data repository (CDIR) of the unique identification authority of India (UIDAI), which is at risk of a single-point fault attack. Perhaps worse, internal attacks can tamper with the sensitive data of authenticated devices without being detected. In this paper, the proposed system utilizes emerging technology: blockchain for solving the issue of centralized authentication. The proposed system provides a distributed, secure, and tamper-proof ledger platform for Aadhar in that Aadhar is implemented using blockchain ethereum technology. The proposed system considers the unique Aadhar identification (ID) for each citizen of India and registered it on the smart contract of ethereum so that this unique ID may be authenticated by each other in a peer-to-peer network without a central authority. For securing the data, the proposed framework uses hashing technique for significant data (i.e. firmware). Blockchain stores hashed data and instantly any change in the state of the data may be possible to detect.
Next I will assess the current health of the asset on the basis of its own fundamentals. You can go to the <strong>“tldr” summary</strong> at the end if you want to skip straight to my conclusions on price predictions. (<em>Disclaimer</em>: This is not financial advice, make sure to always do your own research). Photo by Dmitry Demidko on Unsplash 📊 Macro-Economic Environment In a nutshell the Federal Reserve is under pressure to raise interest rates in order to curb higher than expected inflation figures coming out of the US. This has caused investors to go “risk-off” or in other words get out of riskier assets like stocks and cryptocurrencies. <strong>Netflix</strong> has been the most high-profile name in equities to be hit by this broader market sell-off. The company also reported disappointing subscriber growth figures last Thursday which sent the stock down over 20%. The effects of this downturn have also impacted Bitcoin and the wider crypto market. Bitcoin’s decline below the $40,000 barrier last week is also psychologically important and may cause the price to drop further. The Bank of Russia’s proposal to ban all cryptocurrency activity also appears to have spooked the Bitcoin market and sent prices lower this weekend. But are the fundamentals of Bitcoin sound? Let’s take a look at that in the next sections. <strong>🥇Store of Value: Gold Comparison</strong> Photo by Kanchanara on Unsplash As mentioned in part one, in addition to being a medium of exchange, the second major use-case for Bitcoin is as a store of value. The current market cap of all the gold in the world is valued at <strong>$10 trillion. </strong>Gold obviously has a number of other uses such as in jewellery or certain kinds of industrial manufacturing. But if we run a thought experiment and assume that Bitcoin can get to a market cap of 50% of gold or $5 trillion, what will be the new price? <pre><code>Price = Market Cap / Circulating Supply</code></pre> We know that the maximum total supply of Bitcoin will eventually be <strong>21 million</strong> units (it is currently much lower than this). But if we fast-forward to the future date when the total amount of Bitcoin has been released onto the market we can divide <strong>$5 trillion </strong>by <strong>21 million</strong>. This results in a fairly conservative future price of <strong>$238,095. </strong>The question remains whether Bitcoin will be influenced by short squeeze like traditional stocks. <strong>(Note: </strong>I use the Wolfram Alpha natural language calculator to make it easy to calculate big figure in the trillions and millions without having to remember all the zeros). With the current price of Bitcoin fluctuating around <strong>$35k</strong> this represents a price increase of <strong>580% </strong>or in other words an almost <strong>7x</strong> return. But there are some analysts who don’t view Bitcoin as a replacement for gold. For example, Bitcoin strategist Greg Foss focuses on the bond market as the main target for Bitcoin to take market share. The international bond market is worth well over 10 times that of gold - estimated to be in the region of $119 trillion. If we assume that Bitcoin can attract just 10% of this capital, we get to a figure of <strong>11.9 trillion. </strong>If we run the calculations again and divide <strong>11.9 trillion</strong> by <strong>21 million</strong> we get to a price of: <strong>$566,666.</strong> <strong>📈 Transactions, Market Cap and the NVT Ratio: Paypal Comparison</strong> The one year chart below shows the daily amount of Bitcoin being sent on the network in US dollars. If we ignore the huge spikes in September of around $<strong>310 billion</strong> to <strong>$380 billion</strong>, we can arrive at a conservative average of around <strong>$50 billion</strong> that was sent on the network every day during 2021: Source: bitinfocharts.com To get the annual figure I will simply multiply this <strong>50 billion</strong> by <strong>365</strong> days. This equals: <strong>$18.25 trillion</strong> sent on the Bitcoin network per year. Next we divide Bitcoin’s current market cap at almost $<strong>678 billion</strong> by <strong>$18.25 trillion</strong> to get an annual NVT ratio of <strong>0.037 </strong>(rounded up)<strong>. </strong>In other words, Bitcoin is valued at 3.7% of the money it moves on an annual basis. - <strong>Note:</strong> prices and therefore the market cap changes all time, but these figures are correct at the time of writing on Sunday January 23rd. Now we can compare this NVT figure to other major payment networks in the fiat currency world such as <strong>Paypal</strong> which has a current market cap of $<strong>192 billion:</strong> In Q3 2021 Paypal processed almost <strong>$310 billion </strong>worth of payment transfers: Source: statista.com We can multiply that by 4 to get the rough annual amount of $<strong>1.24 trillion.</strong> So again, <strong>$192 billion</strong> market cap divided by <strong>$1.24 trillion</strong> results in over <strong>0.15 </strong>or trading at <strong>15%</strong> of the dollars it moves annually. Based on these rough calculations it looks like Bitcoin is still very under-valued or under-priced compared to Paypal. 🖥️ Hash Rate: Comparison with other Cryptocurrencies Put simply, the hash rate determines the level of security of a crypto asset which uses proof of work to reach consensus on transactions. As you can see in the all-time chart below, Bitcoin’s hash rate dwarfs that of its main cryptocurrency competitors: The other major assets including Ethereum, Litecoin and Bitcoin Cash in fact barely register on the chart in comparison to Bitcoin. Hash rate is a factor which is often overlooked given that there is nothing equivalent to it in traditional financial markets. But a crypto network will not be very valuable for long if it is not secure, so hash rate is a critical metric to take into consideration. <strong>🎁TLDR: Summary</strong> So, what does this all mean? Based on my store of value analysis, I think it is reasonable to assume that over the long-term (multiple years) Bitcoin can reach a price target of between <strong>$240k</strong> at the low end and <strong>$570k</strong> at the higher end. At the current prices between <strong>$30-35k </strong>(and going lower), this appears to be a good entry point. Of course you have to be willing to tolerate a lot of downside price volatility in the short to medium term, which I define as multiple weeks and months. So I don’t view Bitcoin as a short-term speculative bet. Also I would always advise to put a small percentage of your total net worth in this asset, and only what you can afford to lose. (This is a good rule of thumb for all volatile high-growth assets). Given the value Bitcoin generates in terms of daily transactions compared to Paypal, it also looks under-valued as a payment network. This might also indicate that now is an advantageous time to enter the market for Bitcoin. And lastly, when we look at hash rate we can see just how dominant Bitcoin is in comparison to other leading blockchains which use proof of work. This is also reflected in the recent price movements in the market. Bitcoin continues to be the most stable asset compared to its peers in crypto during market downturns. At the same it offers impressive long-term upside potential. This balance is difficult to find among many other investment types
Complex socio-economic processes are simultaneously taking place in Russian society: the economy is adapting to external economic challenges and, due to the COVID-19 epidemic, many aspects of social life are being transferred online. As a result, there is a transformation of all types of entrepreneurial activity, oriented both to the end consumer and to another legal entity (B2B transactions). The digitalization of commerce objectively requires an effective legal response to the procedures for concluding and executing contracts. A feature of the Russian legal system for regulating digital assets can be considered the impossibility of concluding direct transactions, bypassing a specialized information platform.
 The article discusses the features of smart contracts as a civil law way of disposing of digital rights. The activity of an information platform operator or a market maker as an intermediary is analyzed. Their positive and negative impact on the digital asset market is shown.
 The conclusion is substantiated that the disposal of digital rights through the use of a smart contract cannot be identified with all other classical contractual structures. Smart contracts, including those that are made using blockchain and Ethereum technology, are legally different from the electronic form of a civil law contract. Despite the obvious advantages of a smart contract as a way to manage digital assets, in the absence of legal regulation, significant business risks arise that require a prompt and effective legislative solution
As transaction fees skyrocket today, blockchains become increasingly expensive, hurting their adoption in broader applications. This work tackles the saving of transaction fees for economic blockchain applications. The key insight is that other than the existing "default" mode to execute application logic fully on-chain, i.e., in smart contracts, and in fine granularity, i.e., user request per transaction, there are alternative execution modes with advantages in cost-effectiveness. On Ethereum, we propose a holistic middleware platform supporting flexible and secure transaction executions, including off-chain states and batching of user requests. Furthermore, we propose control-plane schemes to adapt the execution mode to the current workload for optimal runtime cost. We present a case study on the institutional accounts (e.g., coinbase.com) intensively sending Ether on Ethereum blockchains. By collecting real-life transactions, we construct workload benchmarks and show that our work saves 18% ~ 47% per invocation than the default baseline while introducing 1.81 ~ 16.59 blocks delay.
Ignacio Amores-Sesar, Christian Cachin, Tedeschi, Enrico
Avalanche is a blockchain consensus protocol with exceptionally low latency and high throughput. This has swiftly established the corresponding token as a top-tier cryptocurrency. Avalanche achieves such remarkable metrics by substituting proof of work with a random sampling mechanism. The protocol also differs from Bitcoin, Ethereum, and many others by forming a directed acyclic graph (DAG) instead of a chain. It does not totally order all transactions, establishes a partial order among them, and accepts transactions in the DAG that satisfy specific properties. Such parallelism is widely regarded as a technique that increases the efficiency of consensus. Despite its success, Avalanche consensus lacks a complete abstract specification and a matching formal analysis. To address this drawback, this work provides first a detailed formulation of Avalanche through pseudocode. This includes features that are omitted from the original whitepaper or are only vaguely explained in the documentation. Second, the paper gives an analysis of the formal properties fulfilled by Avalanche in the sense of a generic broadcast protocol that only orders related transactions. Last but not least, the analysis reveals a vulnerability that affects the liveness of the protocol. A possible solution that addresses the problem is also proposed.
Existing works on valuing digital assets on the Internet typically focus on a single asset class. To promote the development of automated valuation techniques, preferably those that are generally applicable to multiple asset classes, we construct DASH, the first Digital Asset Sales History dataset that features multiple digital asset classes spanning from classical to blockchain-based ones. Consisting of 280K transactions of domain names (DASH_DN), email addresses (DASH_EA), and non-fungible token (NFT)-based identifiers (DASH_NFT), such as Ethereum Name Service names, DASH advances the field in several aspects: the subsets DASH_DN, DASH_EA, and DASH_NFT are the largest freely accessible domain name transaction dataset, the only publicly available email address transaction dataset, and the first NFT transaction dataset that focuses on identifiers, respectively. We build strong conventional feature-based models as the baselines for DASH. We next explore deep learning models based on fine-tuning pre-trained language models, which have not yet been explored for digital asset valuation in the previous literature. We find that the vanilla fine-tuned model already performs reasonably well, outperforming all but the best-performing baselines. We further propose improvements to make the model more aware of the time sensitivity of transactions and the popularity of assets. Experimental results show that our improved model consistently outperforms all the other models across all asset classes on DASH.
The rapid growth of modern technologies has encouraged non-profit organizations (NPOs) to harness such technologies to better serve the charity sector, especially in relation to charity donation processes. Non-profit organizations primarily rely on fundraising that may involve opaque operations, which leads to the exacerbation of fears that donations may be used for illegal purposes or not reach deserving people. The necessity of charity donations traceability system is inevitable to overcome such concerns, which have an adverse impact on doners’ trust in the donation process. In this study, we propose a blockchain-based donation traceability framework intended to enable all involved parties to trace the progress of charity donations from the moment they are given by donors to the moment they reach the intended recipients. The system is built on a public-permissioned blockchain on the Ethereum platform, with every transaction being recorded as a block in the chain. These blocks of information are immutable and visible to all parties, and they also enable timely and traceable transactions. The proposed framework’s effectiveness is evaluated using a hybrid qualitative approach and proves to improve the traceability of charity donations overcoming the uncertainty associated with current systems.
Abstract This article investigates similarities and differences between gold and four cryptocurrencies (Bitcoin, Ethereum, Bitcoin Cash and Litecoin) with respect to four determinants. To do so, we estimate a system-GARCH-in-mean for the period starting 7/18/2014 at earliest until 7/12/2021. We find that, first, liquidity premia are almost always insignificant for both gold and cryptocurrencies. Second, volatility premia exist in either gold and cryptocurrencies. Third, the response of cryptocurrencies to exchange rate changes is more pronounced than for gold at least if developing countries are included. Fourth, gold exhibits a safe haven status, while cryptocurrencies do not. So according to our results those cannot be seen as a store of value but rather should be seen as speculative assets.
This article explores non-fungible tokens, better known as NFTs, or blockchain-based certificates of ownership for visual or physical assets, a cultural phenomenon which has come to the media attention following the sale of a non-fungible token photo collage, Everyday: The First 5,000 Days, for more than 69 million USD at a Christie's auction in March 2021. The sale made Mike Winkelman (aka Beeple) the third most valuable living artist, behind Jeff Koons and David Hockney starting off a conversation about NFTs which has covered a wide range of issues, including: the contested relationship between art and the market, the long debated question of collective and/or individual authorship within digital aesthetics, the most recent developments in Artificial Intelligence and their creative potential with regard to NFTs – i.e. the appearance of intelligent non-fungible tokens (iNFTs) – and, lastly, the role of cryptocurrencies as a tool for artists’ empowerment or, conversely, as a selling out, under new technological guises, to the capitalist logic of the market. The article reviews and evaluates such debates with the aim to offer critical pointers to help the reader navigate the emerging world of Crypto art.
Yu Han, Xiaolei Wang, Yi Zhang, Gang Yang · 5 authors
In the context of the development of UAVs towards clustering, intelligence, and autonomy, it is necessary to ensure that multiple UAVs and ground control stations can communicate and share information securely in real-time so that UAV swarms can make real-time and effective decisions and collaborations. These factors pose challenges to the security, robustness, and operational efficiency of UAV swarm communication networks. This paper combines blockchain technology with a UAV swarm communication network, proposes a new UAV swarm communication network architecture based on consortium blockchain, and describes the network structure and transaction process in detail. The performance analysis shows that the security mechanism of the architecture can meet the security requirements of the UAV swarm communication network. And this solution is superior to existing solutions based on blockchain technology such as Ethereum in performance and is a technical solution with both security and usability.
Abdul Razzaq, Syed Agha Hassnain Mohsan, Shahbaz Ahmed Khan Ghayyur, Mohammed H. Alsharif · 7 authors
Blockchain technology has emerged as a promising candidate for space exploration and sustainable energy systems. This transformative technology offers secure and decentralized strategies to process and manipulate space resources. Remote sensing provides viable potential with the coexistence of open data from various sources, such as short-range sensors on unmanned aerial vehicles (UAVs) or Internet-of-Things (IoT) tags and far-range sensors incorporated on satellites. Open data resources have most recently emerged as attractive connecting parties where owners have shown consent to share data. However, most data owners are anonymous and untrustworthy, which makes shared data likely insecure and unreliable. At present, there are several tools that distribute open data, serving as an intermediate party to link users with data owners. However, these platforms are operated by central authorities who develop guidelines for data ownership, integrity, and access, consequently restricting both users and data owners. Therefore, the need and feasibility of a decentralized system arise for data sharing and retrieving without involving these intermediate limiting parties. This study proposes a blockchain-based system without any central authority to share and retrieve data. Our proposed system features (i) data sharing, (ii) maintaining the historical data, and (iii) retrieving and evaluation of data along with enhanced security. We have also discussed the use of blockchain algorithms based on smart contracts to track space transactions and communications in a secure, verifiable, and transparent manner. We tested the suggested framework in the Windows environment by writing smart contracts prototype on an Ethereum TESTNET blockchain. The results of the study showed that the suggested strategy is efficient, practicable, and free of common security attacks and vulnerabilities.
Blockchains have seen growing traction with cryptocurrencies reaching a market cap of over 1 trillion dollars, major institution investors taking interests, and global impacts on governments, businesses, and individuals. Also growing significantly is the heterogeneity of the ecosystem where a variety of blockchains co-exist. Cross-chain bridge is a necessary building block in this multi-chain ecosystem. Existing solutions, however, either suffer from performance issues or rely on trust assumptions of committees that significantly lower the security. Recurring attacks against bridges have cost users more than 1.5 billion USD. In this paper, we introduce zkBridge, an efficient cross-chain bridge that guarantees strong security without external trust assumptions. With succinct proofs, zkBridge not only guarantees correctness, but also significantly reduces on-chain verification cost. We propose novel succinct proof protocols that are orders-of-magnitude faster than existing solutions for workload in zkBridge. With a modular design, zkBridge enables a broad spectrum of use cases and capabilities, including message passing, token transferring, and other computational logic operating on state changes from different chains. To demonstrate the practicality of zkBridge, we implemented a prototype bridge from Cosmos to Ethereum, a particularly challenging direction that involves large proof circuits that existing systems cannot efficiently handle. Our evaluation shows that zkBridge achieves practical performance: proof generation takes less than 20 seconds, while verifying proofs on-chain costs less than 230K gas. For completeness, we also implemented and evaluated the direction from Ethereum to other EVM-compatible chains (such as BSC) which involves smaller circuits and incurs much less overhead.
This paper presents Yggdrasil a sharding solution for permissionless blockchains that supports both payment transactions and general Ethereum-like smart contracts. Yggdrasil allows to split and merge shard dynamically leveraging decentralized mechanisms to assign nodes to shards in a secure way. A new 2PC protocol allows to guarantee the execution of smart contracts distributed across different shards even when shards dynamically re-organise. An experimental study confirms the capability of Yggdrasil to scale and to adapt to transaction load.
According to the ever-growing supply and demand of IoT content, IoT big data in diversified applications are deemed a valuable asset by private and public sectors. Their privacy protection has been a hot research topic. Inspired by previous work on bounded-error-pruned IoT content market, we observe that the anonymity protection with robust watermarking can be developed by further pruning data for better resource-efficient IoT big data without violating the required quality of sensor service or quality of decision-making. In this paper, resource-efficient anonymity protection with watermarking is thus proposed for data consumers and owners of IoT big data market via blockchain. Our proposed scheme can provide the IoT data with privacy protections of both anonymity and ownership in IoT big data market with resource efficiency. The experiments of four different-type IoT datasets with different settings included bounded-errors, sub-stream sizes, watermark lengths, and ratios of data tampering. The performance results demonstrated that our proposed scheme can provide data owners and consumers with ownership and anonymity via watermarking the IoT big data streams for lossless compressibility. Meanwhile, the developed DApp with our proposed scheme on the Ethereum blockchain can help data owners freely share and trade with consumers in convenience with availability, reliability, and security without mutual trust.
Open access
Blockchain Technology Applications and Security
Privacy-Preserving Technologies in Data
Advanced Steganography and Watermarking Techniques
L. Remegius Praveen Sahayaraj, Muthurajkumar SANNASY
Agriculture is an art, a craftsmanship and a scientific way of cultivation, growth and maintenance of edible crops and livestock. Majority of the current farming communities do not have prior knowledge of predicting the suitable crop for their soil and climatic conditions. Difficulty in raising the initial investment for crop cultivation is also one of the serious concerns of these communities. The difficulties faced by the civic agriculture, the insecure monetary transactions, along with the concerns related to the financial process have been identified and listed. The paper proposes a feasible solution by predicting the appropriate crops that could be grown in a specific scenario or environmental conditions using the machine-learning model of Support Vector Classifier and provides data related to quality yields using Fuzzy Decision Merkle Tree (FDMT) Regressor. Additionally, a transparent and secure fund transfer mechanism is provided using Ethereum blockchain-based technology. The proposed model implements a secured, translucent and tamper-resistant digital platform for the farming communities to host their products. A fortified consensus can be formed between the farmer and the investor bounded with a rating mechanism to build the credibility of both the farmer and the investor 7 based on the prior knowledge obtained in the Agri-market.