Pemilihan Suara Secara Elektronis Menggunakan Sistem Terdesentralisasi Berbasis Blockchain Ethereum merupakan suatu sistem yang dibuat dalam bentuk aplikasi yang dapat digunakan dalam pemilihan umum. Hal ini dilakukan untuk menyelesaikan masalah yang dimiliki oleh sistem pemilihan suara secara elektronis yang konvensional dimana integritas data belum terjamin dan data hasil suara kemungkinan dapat dirubah oleh pihak tertentu. Masalah ini dapat diselesaikan dengan membuat sistem pemilihan suara secara elektronik yang menyimpan data hasil suara pada blockchain agar integritas data dapat terjamin. Pembuatan sistem ini dilakukan menggunakan bahasa Solidity, bahasa pemrograman yang sudah Turing Complete pada Ethereum. Source code yang dijalankan akan di kompilasi menjadi Bytecode yang kemudian dijalankan pada Ethereum Virtual Machine. Program yang dibuat tersebut kemudian akan di desentralisasi kan menggunakan Blockchain. Hasil nya adalah sistem Electronic Voting yang terdesentralisasi. Sistem ini dapat diakses melalui website https://pemilurt.herokuapp.com/. Abstract Electronic Voting Using Decentralised System Based On Ethereum’s Blockchain is a system made in the form of application used for Electronic Voting. This is done to solve the current problem on conventional electronic voting system where the integrity of the data can’t be ascertain and the result of the vote can be tampered malicious actors. To solve this problem, an electronic voting system will be built that store the data of election results on blockchain to ensure the integrity of the data. The creation of the system involves using the Solidity language, a Turing Complete programming language used on Ethereum. Source code that will be run will first need to be compiled into Bytecode, which will then in turn run on Ethereum Virtual Machine. The finished program will then be decentralised using Blockchain. The result will be a decentralised Electronic Voting system that can be accessed from the website https://pemilurt.herokuapp.com/.
This paper studies three existing technical solutions for a self-sovereign identity on blockchains and analyzes the arising issues related to the General Data Protection Regulation (GDPR) of the European Union (EU). In particular, the paper provides an overview of the existing Sovrin self-sovereign identity on the Hyperledger Indy public permissioned blockchain as well as uPort and Jolocom on the Ethereum public permissionless blockchain. The paper then concludes with a discussion on the GDPR-compliance of the blockchain-based identity concepts.
In recent years we have seen a great deal of attention to the topic of security analysis in smart contracts, especially those developed for the Ethereum blockchain. As a result, there seems to be an evergrowing demand for secure smart contracts to protect what could potentially be worth billions. In this paper, we introduce Etherolic as a robust, scalable and efficient fuzzing tool based on concolic testing for performing security analysis on smart contracts. Our approach works based on a successful combination of dynamic taint tracking (DTA) and concolic testing that allows users to analyze the bytecode of smart contracts being run on the Ethereum Virtual Machine. Moreover, Etherolic is not only able to identify a wide spectrum of recent vulnerabilities in smart contracts, but also it generates exploits to trigger unknown errors in the code. In order to demonstrate the usefulness of our approach, we evaluated Etherolic on a crafted benchmark suite, comprising several real-world and synthetic smart contracts along with 98 safety features. The result of our preliminary evaluation reveals 204 security violations in the benchmarks.
Flooded by the propagation of false or biased news in the Web, people tend to resort to social networks to read posts from reliable sources, exchange commentaries with trustworthy parties, access first-hand content, or cross-check information that appears in news outlets. However, platform providers like Facebook or Twitter can ultimately decide about the contents exposed to each user. Anecdotal evidence suggests that such platform providers are prone to pressure by political or economical agents, and may be ideologically driven to hide messages or block certain users [2, 12] thereby impairing users' ability to freely access rightful information.
Cilj ovog rada je otkriti i proširiti moje znanje o distribuiranim mrežama i teoriji aukcija izradom koncept aplikacije za aukcije na Ethereum mreži koristeći pametne ugovore. Nezamjenjivi tokeni koriste se za stvaranje digitalne povjerljivosti, a prvi put bili su implementirani koristeći Ethereum ERC721 token standard. NFT-Auction-dapp je aplikacija bazirana na Ethereumu koja omogućuje korisnicima da kreiraju i sudjeluju u aukcijama NFT tokena u stvarnom vremenu, na globalnoj i distribuiranoj mreži, zadržavajući garancije plaćanja i dostave. U radu ću se služiti znanjima koja sam stekao tijekom studija na Visokom učilištu Algebra i znanjima koja sam stekao samostalno kako bih izgradio aplikaciju, objavio ju na javnu Ethereum mrežu i testirao njezinu funkcionalnost.
Blockchain-based cryptocurrencies and applications have flourished in blockchain research community. Massive data generated from diverse blockchain systems bring not only huge business values but also technological challenges in data analytics of heterogeneous blockchain data. Different from Bitcoin and Ethereum, EOSIO has richer diversity and a higher volume of blockchain data due to its unique architectural design in resource management, consensus scheme and high throughput. Despite its popularity (e.g., 89,800,000 blocks generated till November 14, 2019 since its launch on June 8, 2018), few studies have been made on data analysis of EOSIO. To fill this gap, we collect and process the up-to-date on-chain data from EOSIO. We name these well-processed EOSIO datasets as XBlock-EOS, which consists of 7 well-processed datasets: 1) Block, Transaction and Action, 2) Internal and External EOS Transfer Action, 3) Contract Information, 4) Contract Invocation, 5) Token Action, 6) Account Creation, 7) Resource Management. It is challenging to process and analyze a high volume of raw EOSIO data and establish the mapping from original raw data to the well-grained datasets since it requires substantial efforts in extracting various types of data as well as sophisticated knowledge on software engineering and data analytics. Meanwhile, we present statistics and exploration on these datasets. Moreover, we also outline the possible research opportunities based on XBlock-EOS.
Yuta Nakamura, Yuanyu Zhang, Masahiro Sasabe, Shoji Kasahara
Due to the rapid penetration of the Internet of Things (IoT) into human life, illegal access to IoT resources (e.g., data and actuators) has greatly threatened our safety. Access control, which specifies who (i.e., subjects) can access what resources (i.e., objects) under what conditions, has been recognized as an effective solution to address this issue. To cope with the distributed and trust-less nature of IoT systems, we propose a decentralized and trustworthy Capability-Based Access Control (CapBAC) scheme by using the Ethereum smart contract technology. In this scheme, a smart contract is created for each object to store and manage the capability tokens (i.e., data structures recording granted access rights) assigned to the related subjects, and also to verify the ownership and validity of the tokens for access control. Different from previous schemes which manage the tokens in units of subjects, i.e., one token per subject, our scheme manages the tokens in units of access rights or actions, i.e., one token per action. Such novel management achieves more fine-grained and flexible capability delegation and also ensures the consistency between the delegation information and the information stored in the tokens. We implemented the proposed CapBAC scheme in a locally constructed Ethereum blockchain network to demonstrate its feasibility. In addition, we measured the monetary cost of our scheme in terms of gas consumption to compare our scheme with the existing Blockchain-Enabled Decentralized Capability-Based Access Control (BlendCAC) scheme proposed by other researchers. The experimental results show that the proposed scheme outperforms the BlendCAC scheme in terms of the flexibility, granularity, and consistency of capability delegation at almost the same monetary cost.
With the rapid popularity of blockchain, decentralized human intelligence tasks (HITs) are proposed to crowdsource human knowledge without relying on vulnerable third-party platforms. However, the inherent limits of blockchain cause decentralized HITs to face a few "new" challenges. For example, the confidentiality of solicited data turns out to be the sine qua non, though it was an arguably dispensable property in the centralized setting. To ensure the "new" requirement of data privacy, existing decentralized HITs use generic zero-knowledge proof frameworks (e.g. SNARK), but scarcely perform well in practice, due to the inherently expensive cost of generality. We present a practical decentralized protocol for HITs, which also achieves the fairness between requesters and workers. At the core of our contributions, we avoid the powerful yet highly-costly generic zk-proof tools and propose a special-purpose scheme to prove the quality of encrypted data. By various non-trivial statement reformations, proving the quality of encrypted data is reduced to efficient verifiable decryption, thus making decentralized HITs practical. Along the way, we rigorously define the ideal functionality of decentralized HITs and then prove the security due to the ideal-real paradigm. We further instantiate our protocol to implement a system called Dragoon, an instance of which is deployed atop Ethereum to facilitate an image annotation task used by ImageNet. Our evaluations demonstrate its practicality: the on-chain handling cost of Dragoon is even less than the handling fee of Amazon's Mechanical Turk for the same ImageNet HIT.
Tianrui Chen, Amjad Saeed Khan, Gan Zheng, Sangarapillai Lambotharan
This letter presents a secure user offloading mechanism in heterogeneous wireless networks (HWNs), where a macrocell base station (MBS) offloads its users to small cell access points (SCAs) using Vickrey auction. Additionally, a user-in-the-loop (UIL) strategy is exploited to encourage the unserved users to move to desired locations for connections. As the participants in the conventional auction-based trading may collude or take selfish actions, we employ Ethereum framework for trustless, secure and distributed auctioning. Simulation results are presented to demonstrate the advantages of the proposed user offloading methodology. The security aspects of the blockchain framework are also discussed.
Smart contracts have enabled blockchain systems to evolve from simple cryptocurrency platforms, such as Bitcoin, to general transactional systems, such as Ethereum. Catering for emerging business requirements, a new architecture called execute-order-validate has been proposed in Hyperledger Fabric to support parallel transactions and improve the blockchain's throughput. However, this new architecture might render many invalid transactions when serializing them. This problem is further exaggerated as the block formation rate is inherently limited due to other factors beside data processing, such as cryptography and consensus. In this work, we propose a novel method to enhance the execute-order-validate architecture, by reducing invalid transactions to improve the throughput of blockchains. Our method is inspired by state-of-the-art optimistic concurrency control techniques in modern database systems. In contrast to existing blockchains that adopt database's preventive approaches which might abort serializable transactions, our method is theoretically more fine-grained. Specifically, unserializable transactions are aborted before ordering and the remaining transactions are guaranteed to be serializable. For evaluation, we implement our method in two blockchains respectively, FabricSharp on top of Hyperledger Fabric, and FastFabricSharp on top of FastFabric. We compare the performance of FabricSharp with vanilla Fabric and three related systems, two of which are respectively implemented with one standard and one state-of-the-art concurrency control techniques from databases. The results demonstrate that FabricSharp achieves 25% higher throughput compared to the other systems in nearly all experimental scenarios. Moreover, the FastFabricSharp's improvement over FastFabric is up to 66%.
Recently, cryptocurrencies such as Bitcoin, Ethereum, etc, have rapidly been recognized as an asset, often called a digital asset. Comparing to the real assets, it would be handled carefully due to its own characteristics that are completely different. The disadvantage of such digital assets, on the one hand, is that whoever knows the private key of the wallet, they can easily take over that digital asset. On the other hand, if the wallet’s owners are dead without passing credential information to others, that asset will be lost forever. We thus propose the novel secure testament methodology for a digital asset such as Bitcoin to solve the mentioned problems. The mechanism is based on managing the mnemonic seed of the wallet so that an inheritor will obtain the mnemonic seed in a secure way. Two mechanisms of the proposed methodology are implemented. The first is to save the mnemonic seed in a secure repository. Therefore, no one can access to the cryptocurrency wallet while the owner still being alive and does not wish anybody to access. The second is to deliver the mnemonic seed securely to legitimate inheritor when the owner is suspected to be dead or disappeared. Finally, based on our experiment, the results show that the aforementioned problems can be solved. Furthermore, the proposed mechanism can help the owner of the asset to managing the confidentiality of their assets.
Advanced Steganography and Watermarking Techniques
There is A finite amount of portable water which is decreasing day by day. Rapid degradation of useful water on earth results in an unkind impact on livelihood. In future, people may have to face (DAY 0) problem therefore, conservation of water is essential. A solution has been proposed to this problem that is “decentralized water management system” using blockchain technology. Blockchain technology can help to use water more efficiently so that every household can lend/borrow the required/extra water from its peer household in the network. In this research work, water ledger architecture has been proposed. This architecture can serve as the basis for Blockchain implementation which can help inbuilding transparency in the water management system with the ultimate goal of Water Conservation. To purpose a system architecture that meets the “demand and supply” of all consumers in a peer-to-peer network so that water can be conserved. A smart contract has been written for transactions (P2P network of 10 household) using Ethereum as a platform. A web interface is created for consumers. Hence, the overall objective is to create a smart water management system for 10 households using blockchain technology to conserve water by medium of sharing water among peer-to-peer as per their needs.
The security and accountability issues are a challenge to the traditional structure from still widespread elections. General e-voting system use a centralized system, where one organization manages overall system. These organisations have full control over the database and system, allowing manipulation of the database. There should be no e-voting system to secure data and potential attacks should be able to withstand. Blockchain technology should solve certain voting problems. In this paper we are implementing an ethereum blockchain based electronic voting system. Ethereum blockchain networks are used to transfer money and store data. Networks are organized by one or more machines. Every node is a machine that running an ethereum client. The eligible one can run the node. By adopting blockchain in e-voting system database distribution, one of the cheating sources of database manipulation and data loss can be reduced. This can be a better solution for the currently existing issues over rigging the electronic voting machines to win elections by the political parties in our government.
Blockchain governance is a subject of ongoing research and an interdisciplinary view of blockchain governance is vital to aid in further research for establishing a formal governance framework for this nascent technology. In this paper, the position of blockchain governance within the hierarchy of Institutional governance is discussed. Blockchain governance is analyzed from the perspective of IT governance using Nash equilibrium to predict the outcome of different governance decisions. A payoff matrix for blockchain governance is created and simulation of different strategy profiles is accomplished for computation of all Nash equilibria. The paper elaborates upon payoff matrices for different kinds of blockchain governance, which are used in the proposition of novel mathematical formulae usable to predict the best governance strategy that minimizes the occurrence of a hard fork as well as predicts the behavior of the majority during protocol updates. The paper also includes validation of the proposed formulae using real Ethereum data.
Blockchain governance is a subject of ongoing research and an interdisciplinary view of blockchain governance is vital to aid in further research for establishing a formal governance framework for this nascent technology. In this paper, the position of blockchain governance within the hierarchy of Institutional governance is discussed. Blockchain governance is analyzed from the perspective of IT governance using Nash equilibrium to predict the outcome of different governance decisions. A payoff matrix for blockchain governance is created and simulation of different strategy profiles is accomplished for computation of all Nash equilibria. The paper elaborates upon payoff matrices for different kinds of blockchain governance, which are used in the proposition of novel mathematical formulae usable to predict the best governance strategy that minimizes the occurrence of a hard fork as well as predicts the behavior of the majority during protocol updates. The paper also includes validation of the proposed formulae using real Ethereum data.
Oscar Delgado-Mohatar, Julián Fiérrez, Rubén Tolosana, Rubén Vera-Rodríguez
Blockchain technologies provide excellent architectures and practical tools for securing and managing the sensitive and private data stored in biometric templates, but at a cost. We discuss opportunities and challenges in the integration of blockchain and biometrics, with emphasis in biometric template storage and protection, a key problem in biometrics still largely unsolved. Key tradeoffs involved in that integration, namely, latency, processing time, economic cost, and biometric performance are experimentally studied through the implementation of a smart contract on the Ethereum blockchain platform, which is publicly available in github for research purposes.
Smart contracts have been a paradigm shift in the realm of business.In the present epoch,smart contracts are a hot potato.Their influence is escalating by leaps and bounds and it is desideratum for the development also.There is paroxysm of interest in cryptocurrency and smart contracts run on ethereum in every nook and corner and it is snowballing on quotidian basis.Firstly,in this research paper,smart contracts and rationale for trusting them is thrashed out.Secondly,this paper expounds the etherum and its cryptocurrency ether.This digital currency has made a leap from an academic concept to virtual reality and is inspiring legion of followers.It has become a de-facto.Thirdly, smart contracts have brobdingnagian gamut of potential application scenarios including both financial as well as non-financial services.Penultimately,this paper delineates the benefits of smart contracts.Lastly,it explicates the challenges thwarting adoption of smart contracts and current scenario of smart contracts in India.This research paper is targeted at providing direction for further research and also,it will serve as a reference for future research papers.
In recent years, many researchers have focused on developing a feasible solution for storing and exchanging medical images in the field of health care. Current practices are deployed on cloud-based centralized data centers, which increase maintenance costs, require massive storage space, and raise privacy concerns about sharing information over a network. Therefore, it is important to design a framework to enable sharing and storing of big medical data efficiently within a trustless environment. In the present paper, we propose a novel proof-of-concept design for a distributed patient-centric image management (PCIM) system that is aimed to ensure safety and control of patient private data without using a centralized infrastructure. In this system, we employed an emerging Ethereum blockchain and a distributed file system technology called Inter-Planetary File System (IPFS). Then, we implemented an Ethereum smart contract called the patient-centric access control protocol to enable a distributed and trustworthy access control policy. IPFS provides the means for decentralized storage of medical images with global accessibility. We describe how the PCIM system architecture facilitates the distributed and secured patient-centric data access across multiple entities such as hospitals, patients, and image requestors. Finally, we deployed a smart contract prototype on an Ethereum testnet blockchain and evaluated the proposed framework within the Windows environment. The evaluation results demonstrated that the proposed scheme is efficient and feasible.
Purpose The authors develop new quantitative methods to estimate the level of speculation and long-term sustainability of Bitcoin and Blockchain. Design/methodology/approach The authors explore the practical application of speculative bubble models to cryptocurrencies. They then show how the approach can be extended to provide estimated brand values using data from Google Trends. Findings The authors confirm previous findings of speculative bubbles in cryptocurrency markets. Relatedly, Google searches for cryptocurrencies seem to be primarily driven by recent price rises. Overall results are sufficient to question the long-term sustainability of Bitcoin with the suggestion that Ethereum, Bitcoin Cash and Ripple may all enjoy technical advantages relative to Bitcoin. Our results also demonstrate that Blockchain has a distinct value and identity beyond cryptocurrencies – providing foundational support for the second generation of academic work on Blockchain. However, a relatively low estimated long-term growth rate suggests that the benefits of Blockchain may take a long time to be fully realised. Originality/value The authors contribute to an emerging academic literature on Blockchain and to a more established literature exploring the use of Google data within business analytics. Their original contribution is to quantify the business value of Blockchain and related technologies using Google Trends