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Zhou, Chencheng, Liudong Xing, Qisi Liu, and Honggang Wang. "Semi-Markov Based Dependability Modeling of Bitcoin Nodes Under Eclipse Attacks and State-Dependent Mitigation." International Journal of Mathematical, Engineering and Management Sciences 6, no. 2 (2021): 480–92. http://dx.doi.org/10.33889/ijmems.2021.6.2.029.
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The block chain technology has immense potential in many different applications, including but not limited to cryptocurrencies, financial services, smart contracts, supply chains, healthcare services, and energy trading. Due to the critical nature of these applications, it is pivotal to model and evaluate dependability of the block chain-based systems, contributing to their reliable and robust operation. This paper models and analyzes the dependability of Bitcoin nodes subject to Eclipse attacks and state-dependent mitigation activities. Built upon the block chain technology, the Bitcoin is a peer-to-peer cryptocurrency system enabling an individual user to trade freely without the involvement of banks or any other types of intermediate agents. However, a node in the Bitcoin is vulnerable to the Eclipse attack, which aims to monopolize the information flow of the victim node. A semi-Markov process (SMP) based approach is proposed to model the Eclipse attack behavior and possible mitigation activities that may prevent the attack from being successful during the attack process. The SMP model is then evaluated to determine the steady-state dependability of the Bitcoin node. Numerical examples are provided to demonstrate the influence of the time to restart the Bitcoin software and time to detect and delete the malicious message on the Bitcoin node dependability.
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Pazmiño, Juan Eduardo, and Carlo Kleber da Silva Rodrigues. "Simply Dividing a Bitcoin Network Node may Reduce Transaction Verification Time." SIJ Transactions on Computer Networks & Communication Engineering 03, no. 01 (2015): 01–05. http://dx.doi.org/10.9756/sijcnce/v3i1/03020020101.
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Al-Haija, Qasem Abu, and Abdulaziz A. Alsulami. "High Performance Classification Model to Identify Ransomware Payments for Heterogeneous Bitcoin Networks." Electronics 10, no. 17 (2021): 2113. http://dx.doi.org/10.3390/electronics10172113.
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The Bitcoin cryptocurrency is a worldwide prevalent virtualized digital currency conceptualized in 2008 as a distributed transactions system. Bitcoin transactions make use of peer-to-peer network nodes without a third-party intermediary, and the transactions can be verified by the node. Although Bitcoin networks have exhibited high efficiency in the financial transaction systems, their payment transactions are vulnerable to several ransomware attacks. For that reason, investigators have been working on developing ransomware payment identification techniques for bitcoin transactions’ networks to prevent such harmful cyberattacks. In this paper, we propose a high performance Bitcoin transaction predictive system that investigates the Bitcoin payment transactions to learn data patterns that can recognize and classify ransomware payments for heterogeneous bitcoin networks. Specifically, our system makes use of two supervised machine learning methods to learn the distinguishing patterns in Bitcoin payment transactions, namely, shallow neural networks (SNN) and optimizable decision trees (ODT). To validate the effectiveness of our solution approach, we evaluate our machine learning based predictive models on a recent Bitcoin transactions dataset in terms of classification accuracy as a key performance indicator and other key evaluation metrics such as the confusion matrix, positive predictive value, true positive rate, and the corresponding prediction errors. As a result, our superlative experimental result was registered to the model-based decision trees scoring 99.9% and 99.4% classification detection (two-class classifier) and accuracy (multiclass classifier), respectively. Hence, the obtained model accuracy results are superior as they surpassed many state-of-the-art models developed to identify ransomware payments in bitcoin transactions.
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Schreiber, Zvi. "k-Root-n: An Efficient Algorithm for Avoiding Short Term Double-Spending Alongside Distributed Ledger Technologies such as Blockchain." Information 11, no. 2 (2020): 90. http://dx.doi.org/10.3390/info11020090.
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Blockchains such as the bitcoin blockchain depend on reaching a global consensus on the distributed ledger; therefore, they suffer from well-known scalability problems. This paper proposes an algorithm that avoids double-spending in the short term with just O(√n) messages instead of O(n); each node receiving money off-chain performs the due diligence of consulting k√n random nodes to check if any of them is aware of double-spending. Two nodes receiving double-spent money will in this way consult at least one common node with very high probability, because of the ‘birthday paradox’, and any common honest node consulted will detect the fraud. Since the velocity of money in the real world has coins circulating through at most a few wallets per day, the size of the due diligence communication is small in the short term. This ‘k-root-n’ algorithm is suitable for an environment with synchronous or asynchronous (but with fairly low latency) communication and with Byzantine faults. The presented k-root-n algorithm should be practical to avoid double-spending with arbitrarily high probability, while feasibly coping with the throughput of all world commerce. It is resistant to Sybil attacks even beyond 50% of nodes. In the long term, the k-root-n algorithm is less efficient. Therefore, it should preferably be used as a complement, and not a replacement, to a global distributed ledger technology.
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Ge, Lin, and Tao Jiang. "A Privacy Protection Method of Lightweight Nodes in Blockchain." Security and Communication Networks 2021 (July 15, 2021): 1–17. http://dx.doi.org/10.1155/2021/2067137.
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Aiming at the privacy protection of lightweight nodes based on Bloom filters in blockchain, this paper proposes a new privacy protection method. Considering the superimposition effect of query information, node and Bloom filter are regarded as the two parties of the game. A privacy protection mechanism based on the mixed strategy Nash equilibrium is proposed to judge the information query. On this basis, a Bloom filter privacy protection algorithm is proposed when the probability of information query and privacy, not being leaked, is less than the node privacy protection. It is based on variable factor disturbance, adjusting the number of bits’ set to 1 in the Bloom filter to improve the privacy protection performance in different scenarios. The experiment uses Bitcoin transaction data from 2009 to 2019 as the test data to verify the effectiveness, reliability, and superiority of the method.
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Motlagh, Saeideh G., Jelena Misic, and Vojislav B. Misic. "Impact of Node Churn in the Bitcoin Network." IEEE Transactions on Network Science and Engineering 7, no. 3 (2020): 2104–13. http://dx.doi.org/10.1109/tnse.2020.2974739.
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Cao, Jiangdong, and Wei Cao. "Bitcoin mining, the way to process transaction information or the way to make money?" INSIST 4, no. 1 (2019): 191. http://dx.doi.org/10.23960/ins.v4i1.191.
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Bitcoin is a crypto currency introduced by Satoshi Nakamoto in 2008. It has the features of decentralization cross-border and fixed total amount and has become one of the most widely used crypto-currencies. Bitcoin, as a new digital currency system, innovatively makes the use of cryptographic elements and consensus mechanisms and builds up a secure decentralized system. The Blockchain, as the core of Bitcoin, uses peer-to-peer network communications and backs up transaction data in every node of the system, thus creating a huge distributed public book. It is essentially a decentralized distributed ledger database, and the decentralization means that the transaction is broadcast to the entire network, where everyone is involved in book keeping. In order to make every participant in the Blockchain willing to participate in the bookkeeping, the reward mechanism of the Bitcoin system is mining. This article first introduces the concept of Blockchain technology, then expounds the principle and the operation mechanism of the Bitcoin and the Bitcoin mining principle, introduces an example of Bitcoin mining in-depth study and analysis, finally, summarize and prospect the development of the Bitcoin mining.
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Zize, Zhang. "Analysis on Criminal Governance of Bitcoin-related Corruption Cases." Economics, Law and Policy 4, no. 1 (2021): p37. http://dx.doi.org/10.22158/elp.v4n1p37.
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Bitcoin is extremely easy to be used in corruption cases due to its pseudonym, easy circulation, easy cross-border and other characteristics. As a decentralized electronic account book, the circulation of regulatory funds is jointly confirmed by each node in the bitcoin network, which can ensure the authenticity of the criminal evidence and is not easy to be lost or damaged. It provides great convenience for evidence collection in bitcoin corruption cases. However, there are also shackles in criminal governance, such as how to prove the subjective intent of the bribe takers, the impact of fluctuations in market value on the identification of the case and, most importantly, how to effectively recover stolen goods across borders. Therefore, the difficulty of bitcoin-related cases does not lie in the “anonymity” that some scholars believe, but lies in the determination of subjective intent, the determination of the amount of the crime and the international judicial assistance in recovering the stolen money.
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Oggier, Frédérique, Silivanxay Phetsouvanh, and Anwitaman Datta. "A split-and-transfer flow based entropic centrality." PeerJ Computer Science 5 (September 16, 2019): e220. http://dx.doi.org/10.7717/peerj-cs.220.
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The notion of entropic centrality measures how central a node is in terms of how uncertain the destination of a flow starting at this node is: the more uncertain the destination, the more well connected and thus central the node is deemed. This implicitly assumes that the flow is indivisible, and at every node, the flow is transferred from one edge to another. The contribution of this paper is to propose a split-and-transfer flow model for entropic centrality, where at every node, the flow can actually be arbitrarily split across choices of neighbours. We show how to map this to an equivalent transfer entropic centrality set-up for the ease of computation, and carry out three case studies (an airport network, a cross-shareholding network and a Bitcoin transactions subnetwork) to illustrate the interpretation and insights linked to this new notion of centrality.
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Le, Duc V., Lizzy Tengana Hurtado, Adil Ahmad, Mohsen Minaei, Byoungyoung Lee, and Aniket Kate. "A Tale of Two Trees: One Writes, and Other Reads." Proceedings on Privacy Enhancing Technologies 2020, no. 2 (2020): 519–36. http://dx.doi.org/10.2478/popets-2020-0039.
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AbstractThe Bitcoin network has offered a new way of securely performing financial transactions over the insecure network. Nevertheless, this ability comes with the cost of storing a large (distributed) ledger, which has become unsuitable for personal devices of any kind. Although the simplified payment verification (SPV) clients can address this storage issue, a Bitcoin SPV client has to rely on other Bitcoin nodes to obtain its transaction history and the current approaches offer no privacy guarantees to the SPV clients.This work presents T3, a trusted hardware-secured Bitcoin full client that supports efficient oblivious search/update for Bitcoin SPV clients without sacrificing the privacy of the clients. In this design, we leverage the trusted execution and attestation capabilities of a trusted execution environment (TEE) and the ability to hide access patterns of oblivious random access machine (ORAM) to protect SPV clients’ requests from potentially malicious nodes. The key novelty of T3 lies in the optimizations introduced to conventional ORAM, tailored for expected SPV client usages. In particular, by making a natural assumption about the access patterns of SPV clients, we are able to propose a two-tree ORAM construction that overcomes the concurrency limitation associated with traditional ORAMs. We have implemented and tested our system using the current Bitcoin Unspent Transaction Output (UTXO) Set. Our experiment shows that T3 is feasible to be deployed in practice while providing strong privacy and security guarantees to Bitcoin SPV clients.
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Turner, Adam, and Angela Samantha Maitland Irwin. "Bitcoin transactions: a digital discovery of illicit activity on the blockchain." Journal of Financial Crime 25, no. 1 (2018): 109–30. http://dx.doi.org/10.1108/jfc-12-2016-0078.
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Purpose The purpose of this paper is to determine if Bitcoin transactions could be de-anonymised by analysing the Bitcoin blockchain and transactions conducted through the blockchain. In addition, graph analysis and the use of modern social media technology were examined to determine how they may help reveal the identity of Bitcoin users. A review of machine learning techniques and heuristics was carried out to learn how certain behaviours from the Bitcoin network could be augmented with social media technology and other data to identify illicit transactions. Design/methodology/approach A number of experiments were conducted and time was spend observing the network to ascertain how Bitcoin transactions work, how the Bitcoin protocol operates over the network and what Bitcoin artefacts can be examined from a digital forensics perspective. Packet sniffing software, Wireshark, was used to see whether the identity of a user is revealed when they set up a wallet via an online wallet service. In addition, a block parser was used to analyse the Bitcoin client synchronisation and reveal information on the behaviour of a Bitcoin node when it joins the network and synchronises to the latest blockchain. The final experiment involved setting up and witnessing a transaction using the Bitcoin Client API. These experiments and observations were then used to design a proof of concept and functional software architecture for searching, indexing and analyzing publicly available data flowing from the blockchain and other big data sources. Findings Using heuristics and graph analysis techniques show us that it is possible to build up a picture of behaviour of Bitcoin addresses and transactions, then utilise existing typologies of illicit behaviour to collect, process and exploit potential red flag indicators. Augmenting Bitcoin data, big data and social media may be used to reveal potentially illicit financial transaction going through the Bitcoin blockchain and machine learning applied to the data sets to rank and cluster suspicious transactions. Originality/value The development of a functional software architecture that, in theory, could be used to detect suspicious illicit transactions on the Bitcoin network.
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Yao, Yuhang, Xiao Zeng, Tianyue Cao, Luoyi Fu, and Xinbing Wang. "APRP: An Anonymous Propagation Method in Bitcoin Network." Proceedings of the AAAI Conference on Artificial Intelligence 33 (July 17, 2019): 10073–74. http://dx.doi.org/10.1609/aaai.v33i01.330110073.
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Due to little attention given to anonymous protection against eavesdropping attacks in Bitcoin network, this paper initiatively proposes a solution to Bitcoin anonymization based on network structure. We first present a general adversarial network model for formulizing deanonymization attack, then present a novel propagation method APRP(Adaptive PageRank Propagation) that adopts PageRank as propagation delay factor and constantly adjusts PR-value of nodes to adapt to network dynamics. Experiments on both simulated and real Bitcoin networks confirm the superiority of APRP in terms of 20-50% performance enhancement under various deanonymization attacks.
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Park, Youngho, Chul Sur, and Kyung-Hyune Rhee. "A Secure Incentive Scheme for Vehicular Delay Tolerant Networks Using Cryptocurrency." Security and Communication Networks 2018 (July 8, 2018): 1–13. http://dx.doi.org/10.1155/2018/5932183.
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One remarkable feature of vehicular ad hoc networks is characterized by an opportunistic communications by means of store-carry-forward message relaying which requires the cooperation of vehicles on the networks. However, we cannot be sure that all vehicles willingly contribute their computing resources to the networks for message forwarding with no rewards for their efforts in real-world scenarios. In addition, unfortunately, there may exist some selfish and greedy node which may not help others but tend to take their own gain. To cope with this challenge, incentive mechanisms are generally considered as the promising solution. In this paper, we design a Bitcoin-based secure and reliable incentive scheme for cooperative vehicular delay tolerant networking services. Bitcoin is the well-known worldwide cryptocurrency and digital payment system whose implementation relies on cryptographic techniques, which makes it possible to develop a practical credit-based incentive scheme on the vehicular networks at a low cost. We also implement Bitcoin transaction scripts to handle our proposed incentive scheme.
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Houy, Nicolas. "The Bitcoin Mining Game." Ledger 1 (December 21, 2016): 53–68. http://dx.doi.org/10.5195/ledger.2016.13.
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This article deals with the mining incentives in the Bitcoin protocol. The mining process is used to confirm and secure transactions. This process is organized as a speed game between individuals or firms – the miners – with different computational powers to solve a mathematical problem, bring a proof of work, spread their solution and reach consensus among the Bitcoin network nodes with it. First, we define and specify this game. Second, we analytically find its Nash equilibria in the two-player case. We analyze the parameters for which the miners would face the proper incentives to fulfill their function of transaction processors in the current situation. Finally, we study the block space market offer.
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Burchert, Conrad, Christian Decker, and Roger Wattenhofer. "Scalable funding of Bitcoin micropayment channel networks." Royal Society Open Science 5, no. 8 (2018): 180089. http://dx.doi.org/10.1098/rsos.180089.
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The Bitcoin network has scalability problems. To increase its transaction rate and speed, micropayment channel networks have been proposed; however, these require to lock funds into specific channels. Moreover, the available space in the blockchain does not allow scaling to a worldwide payment system. We propose a new layer that sits in between the blockchain and the payment channels. The new layer addresses the scalability problem by enabling trustless off-blockchain channel funding. It consists of shared accounts of groups of nodes that flexibly create one-to-one channels for the payment network. The new system allows rapid changes of the allocation of funds to channels and reduces the cost of opening new channels. Instead of one blockchain transaction per channel, each user only needs one transaction to enter a group of nodes—within the group the user can create arbitrarily many channels. For a group of 20 users with 100 intra-group channels, the cost of the blockchain transactions is reduced by 90% compared to 100 regular micropayment channels opened on the blockchain. This can be increased further to 96% if Bitcoin introduces Schnorr signatures with signature aggregation.
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Longo, Riccardo, Alessandro Sebastian Podda, and Roberto Saia. "Analysis of a Consensus Protocol for Extending Consistent Subchains on the Bitcoin Blockchain." Computation 8, no. 3 (2020): 67. http://dx.doi.org/10.3390/computation8030067.
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Currently, an increasing number of third-party applications exploit the Bitcoin blockchain to store tamper-proof records of their executions, immutably. For this purpose, they leverage the few extra bytes available for encoding custom metadata in Bitcoin transactions. A sequence of records of the same application can thus be abstracted as a stand-alone subchain inside the Bitcoin blockchain. However, several existing approaches do not make any assumptions about the consistency of their subchains, either (i) neglecting the possibility that this sequence of messages can be altered, mainly due to unhandled concurrency, network malfunctions, application bugs, or malicious users, or (ii) giving weak guarantees about their security. To tackle this issue, in this paper, we propose an improved version of a consensus protocol formalized in our previous work, built on top of the Bitcoin protocol, to incentivize third-party nodes to consistently extend their subchains. Besides, we perform an extensive analysis of this protocol, both defining its properties and presenting some real-world attack scenarios, to show how its specific design choices and parameter configurations can be crucial to prevent malicious practices.
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Pagalla Bhavani Shankar. "Blockchain: The Essential Future of Modern Internet." International Journal for Modern Trends in Science and Technology 6, no. 10 (2020): 60–64. http://dx.doi.org/10.46501/ijmtst061011.
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This paper deals with the future of modern internet, named as “Blockchain”. Blockchain is renowned as the worlds populating a type of new software platform for all kinds of digital assets. In a form of, forms of blocks data will be stored or recorded in blockchain, and emerged & protected and secured by the conceptual of Cryptography. After release of bitcoin, the “Modern Internet : Blockchain” became a high peak internet protocol , which is transforming the values of data from a node to node in a block and working in a decentralized manner. Blockchain is a state of art technology that is always associated with a great level (layer) of security and privacy In today’s tremendous technology innovations, blockchain technology is not only implemented in crypto-currencies , but also in social and corporate segments too, like e-commerce, e-governance, logistics and many others.
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Park, Sehyun, Seongwon Im, Youhwan Seol, and Jeongyeup Paek. "Nodes in the Bitcoin Network: Comparative Measurement Study and Survey." IEEE Access 7 (2019): 57009–22. http://dx.doi.org/10.1109/access.2019.2914098.
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Maram, Balajee. "Bitcoin Generation using Blockchain Technology." JOIV : International Journal on Informatics Visualization 2, no. 3 (2018): 127. http://dx.doi.org/10.30630/joiv.2.3.109.
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There are limitations in client-server model of communication. Distributed architecture provides good accessibility to all the nodes in the network. A blockchain technology is follows distributed model. In the digital era, all the transactions are available in the digital form is called a ledger. This ledger belongs to all the users in the network are shared by all the users in the network. Every transaction is monitored and verified by every user in the network. The blockchain is a chain of blocks that contains a collection of transactions. Bitcoin is a cryptocurrency, depends on blockchain technology. The Bitcoins are generated from the mining of a block for the miner. Every user knows about each and every Bitcoin transaction in the blockchain network. The block is immutable, because every block is verified by each customer in the blockchain network. This is the initiation for new trend for security to the digital transactions in the world. This paper presents the logic in the blockchain and Bitcoin generation process using blockchain technology.
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Berdugo, Liat Rachel, and Emily Martinez. "Seeing Blocks and Crypto Bros." Media-N 16, no. 1 (2020): 79–98. http://dx.doi.org/10.21900/j.median.v16i1.225.
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How do cryptocurrencies like Bitcoin work? What is a blockchain? And, what does a typical Bitcoin holder look like? The artist collective Anxious to Make commissioned sixty cloudworkers to draw their answers to these questions. Drawings range from the mundane and stereotypical—a Bitcoin owner depicted as a bearded hipster shouting, HODL!—to the complex and eccentric—the blockchain drawn as connected nodes of random numbers, presumably meant to represent cryptographic hashes. 
 Like much technology, the inner workings of cryptocurrency remain “black boxes” of understanding to most users. As a collective, Anxious to Make remains cautious of any technological apparatus that is believed in without understanding. These series of drawings point to the absurdity and comic nature of technological beliefs and utopic, seamless crypto-fantasies. We offer a subset of the drawings here, together with an analysis of the ways artistic labor is changed by—or mirrors—the practice of outsourcing.
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Nabilou, Hossein. "How to regulate bitcoin? Decentralized regulation for a decentralized cryptocurrency." International Journal of Law and Information Technology 27, no. 3 (2019): 266–91. http://dx.doi.org/10.1093/ijlit/eaz008.
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Abstract Bitcoin is a distributed system. The dilemma it poses to the legal systems is that it is hardly possible to regulate a distributed network in a centralized fashion, as decentralized cryptocurrencies are antithetical to the existing centralized structure of monetary and financial regulation. This article proposes a more nuanced policy recommendation for regulatory intervention in the cryptocurrency ecosystem, which relies on a decentralized regulatory architecture built upon the existing regulatory infrastructure and makes use of the existing and emerging middlemen. It argues that instead of regulating the technology or the cryptocurrencies at the code or protocol layer, the regulation should target their use-cases. Such a regulatory strategy can be implemented through directing the edicts of regulation towards the middlemen and can be enforced by the existing financial market participants and traditional gatekeepers such as banks, payment service providers and exchanges, as well as large and centralized node operators and miners.
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Chapnevis, Amirahmad, Abouzar Arabsorkhi, and Tala Tafazzoli. "An automated method for detecting suspicious nodes in Bitcoin address graph." International Journal of Security and Networks 1, no. 1 (2020): 1. http://dx.doi.org/10.1504/ijsn.2020.10039019.
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Zhang, Zhen, Bing Guo, Yan Shen, Chengjie Li, Xinhua Suo, and Hong Su. "Nakamoto Consensus to Accelerate Supervised Classification Algorithms for Multiparty Computing." Security and Communication Networks 2021 (March 11, 2021): 1–11. http://dx.doi.org/10.1155/2021/6629433.
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Bitcoin mining consumes tremendous amounts of electricity to solve the hash problem. At the same time, large-scale applications of artificial intelligence (AI) require efficient and secure computing. There are many computing devices in use, and the hardware resources are highly heterogeneous. This means a cooperation mechanism is needed to realize cooperation among computing devices, and a good calculation structure is required in the case of data dispersion. In this paper, we propose an architecture where devices (also called nodes) can reach a consensus on task results using off-chain smart contracts and private data. The proposed distributed computing architecture can accelerate computing-intensive and data-intensive supervised classification algorithms with limited resources. This architecture can significantly increase privacy protection and prevent leakage of distributed data. Our proposed architecture can support heterogeneous data, making computing on each device more efficient. We used mathematical formulas to prove the correctness and robustness of our system and deduced the condition to stop a given task. In the experiments, we transformed Bitcoin hash collision into distributed computing on several nodes and evaluated the training and prediction accuracy for handwritten digit images (MNIST). The experimental results demonstrate the effectiveness of the proposed method.
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Wu, Nannan, Wenjun Wang, Feng Chen, Jianxin Li, Bo Li, and Jinpeng Huai. "Uncovering Specific-Shape Graph Anomalies in Attributed Graphs." Proceedings of the AAAI Conference on Artificial Intelligence 33 (July 17, 2019): 5433–40. http://dx.doi.org/10.1609/aaai.v33i01.33015433.
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As networks are ubiquitous in the modern era, point anomalies have been changed to graph anomalies in terms of anomaly shapes. However, the specific-shape priors about anomalous subgraphs of interest are seldom considered by the traditional approaches when detecting the subgraphs in attributed graphs (e.g., computer networks, Bitcoin networks, and etc.). This paper proposes a nonlinear approach to specific-shape graph anomaly detection. The nonlinear approach focuses on optimizing a broad class of nonlinear cost functions via specific-shape constraints in attributed graphs. Our approach can be used to many different graph anomaly settings. The traditional approaches can only support linear cost functions (e.g., an aggregation function for the summation of node weights). However, our approach can employ more powerful nonlinear cost functions, and enjoys a rigorous theoretical guarantee on the near-optimal solution with the geometrical convergence rate.
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Motlagh, Saeideh G., Jelena Mišić, and Vojislav B. Mišić. "An analytical model for churn process in Bitcoin network with ordinary and relay nodes." Peer-to-Peer Networking and Applications 13, no. 6 (2020): 1931–42. http://dx.doi.org/10.1007/s12083-020-00953-y.
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Misic, Jelena, Vojislav B. Misic, and Xiaolin Chang. "Performance of Bitcoin Network With Synchronizing Nodes and a Mix of Regular and Compact Blocks." IEEE Transactions on Network Science and Engineering 7, no. 4 (2020): 3135–47. http://dx.doi.org/10.1109/tnse.2020.3017453.
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Heo, Hwanjo, and Seungwon Shin. "Understanding Block and Transaction Logs of Permissionless Blockchain Networks." Security and Communication Networks 2021 (August 3, 2021): 1–18. http://dx.doi.org/10.1155/2021/9549602.
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Public blockchain records are widely studied in various aspects such as cryptocurrency abuse, anti-money-laundering, and monetary flow of businesses. However, the final blockchain records, usually available from block explorer services or querying locally stored data of blockchain nodes, do not provide abundant and dynamic event logs that are only visible from a live large-scale measurement. In this paper, we collect the network logs of three popular permissionless blockchains, that is, Bitcoin, Ethereum, and EOS. The discrepancy between observed events and the public block data is studied via a noble analysis model provided with the soundness of measurement. We share our key findings including a false universal assumption of previous mining-related studies and the block/transaction arrival characteristics.
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Nowostawski, Mariusz, and Jardar Tøn. "Evaluating Methods for the Identification of Off-Chain Transactions in the Lightning Network." Applied Sciences 9, no. 12 (2019): 2519. http://dx.doi.org/10.3390/app9122519.
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Payment channels and off-chain transactions are used to address blockchain scalability. Those mechanisms rely on the blockchain proper, as the resolution mechanism. They allow for high transaction throughput due to the pure peer-to-peer nature of the transaction exchange that happens directly between the peers, without the involvement of the blockchain transactions. The transactions are not mediated through the blockchain but happen off-chain. The transactions in such overlay networks are not included in the blockchain, they nevertheless leave some data traces in a public ledger. We have used the Bitcoin mainnet and testnet blockchains together with the Lightning network node to explore what can be inferred from the underlying blockchain in the context of Lightning transactions, channel setup, and channel teardown. The main purpose of this study is to identify what methods, transaction signatures, and data can be used to understand the non-visible publicly off-chain transactions. We have proposed heuristics for identifying the setup and teardown transactions, quantified and analyzed the effectiveness of our proposed methods. Using the data from the Bitcoin blockchain, as well as the data from the Lightning network to link related information we have found when parsing the blockchain, we generate network graph representations showing the relationships between the Lightning network channels identified on the blockchain. This study is significant from the personal data and privacy perspectives, as well as from forensics. We have established that at least 75% of all P2WSH transactions are Lightning transactions, and some of the channels can be deduced from the blockchain analysis. The synthesized results demonstrate that our methods are viable for identifying a subset of transactions and that only partial topology of the payment channels can be obtained from the data left in the blockchain.
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Derbentsev, Vasily D., Vitalii S. Bezkorovainyi, and Iryna V. Luniak. "Application of Deep Learning Methods to Forecasting Changes in Short-Term Currency Trends." Scientific Bulletin of Mukachevo State University Series “Economics” 7, no. 2 (2020): 75–86. http://dx.doi.org/10.52566/msu-econ.7(2).2020.75-86.
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This study investigates the issues of forecasting changes in short-term currency trends using deep learning models, which is relevant for both the scientific community and for traders and investors. The purpose of this study is to build a model for forecasting the direction of change in the prices of currency quotes based on deep neural networks. The developed architecture was based on the model of valve recurrent node, which is a modification of the model of “Long Short-Term Memory”, but is simpler in terms of the number of parameters and learning time. The forecast calculations of the dynamics of quotations of the currency pair euro/dollar and the most capitalised cryptocurrency Bitcoin/dollar were performed using daily, four-hour and hourly datasets. The obtained results of binary classification (forecast of the direction of trend change) when applying daily and hourly quotations turned out to be generally better than those of time series models or models of neural networks of other architecture (in particular, multilayer perceptron or “Long Short-Term Memory” models). According to the study results, the highest accuracy of classification was for the model of daily quotations for both euro/dollar – about 72%, and for Bitcoin/ dollar – about 69%. For four-hour and hourly time series, the accuracy of classification decreased, which can be explained both by the increase in the impact of “market noise” and the probable overfitting. Computer simulation has demonstrated that models predict a rising trend better than a declining one. The study confirmed the prospects for the application of deep learning models for short-term forecasting of time series of currency quotes. The use of the developed models proved to be effective for both fiat and cryptocurrencies. The proposed system of models based on deep neural networks can be used as a basis for developing an automated trading system in the foreign exchange market
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Ferreira, Micael, Sven Rodrigues, Catarina Reis, and Marisa Maximiano. "Blockchain: A Tale of Two Applications." Applied Sciences 8, no. 9 (2018): 1506. http://dx.doi.org/10.3390/app8091506.
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Bitcoin continues to get more and more attention from the media, mainly because of the volatility of its value and insignificantly associated with the technological innovation. This cryptocurrency is supported by an immutable database and is distributed throughout a network of thousands of nodes, known as Blockchain. One way to ensure that all the concepts behind the Blockchain technology and infrastructure are seized is to conduct the development of one of the most popular context applications for it: a wallet for well-known cryptocurrencies. Yet Another Bitcoin Wallet (YABW) is a hybrid application available for both Android and iOS, which was developed with the Ionic and Angular frameworks. This application communicates with Bitcoin Blockchain to send, receive and store bitcoins; provides a set of features focused on security and user experience, and is available on the Play Store and Apple Store. A rather relevant issue that is becoming a major subject of current research is the application of the Blockchain infrastructure to other contexts that are neither directly connected to cryptocurrencies, nor are finance related. The implementation of a proof-of-concept application proposes the use of a blockchain for a specific case study: the exchange of meal vouchers of an institution amongst students. This is achieved using the decentralized platform Ethereum, which allows us to create a Smart Contract using the Solidity programming language to create a token that follows the Ethereum Request for Comment (ERC), the ERC-20 standard and represents the meal vouchers. This second application uses the architecture defined for YABW, reusing major components and custom developing specific modules to enhance the required features. There is still a lot of research to be done on the non-financial applicability of the Blockchain infrastructure and technology, but for the moment, we have left further evidence that it is possible and is a relative straight-forward process to accomplish from the technological perspective.
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Shevchuk, Oksana, and Natalia Mentuh. "MAIN MECHANISMS OF MONETARY POLICY IMPLEMENTATION AND THEIR FEATURES." Scientific Notes Series Law 1, no. 9 (2020): 115–21. http://dx.doi.org/10.36550/2522-9230-2020-1-9-115-121.
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This scientific article is devoted to the analysis of theoretical principles, legislation, scientific positions on improving the priorities and mechanisms of monetary policy in the national financial security system. The purpose of the study is to strengthen the process of national financial security. The subject of the study is to identify key points in the national financial security system and the implementation of theoretical and methodological principles, as well as scientific and practical recommendations for the implementation of mechanisms to improve monetary policy. The conceptual provisions of monetary policy and its provisions in the national system of economic and financial security are formulated. The authors substantiate that today the financial systems of individual countries, as well as other sectors of the economy, are improving and progressing in the context of globalization, the spread of IT technologies and general computerization; Electronic cryptocurrency replaces traditional money issued by the state. It is substantiated that over the last year the cryptocurrency has won the interest not only of people, but of entire states, which have begun to actively introduce this currency into their daily circulation. This means of payment is already gaining momentum in use in developed countries. The focus is on the analysis of the concept of "blockchain". The article states that today Ukraine is among the ten countries in the world in the number of bitcoin nodes in the global bitcoin network, the leader in the number of bitcoin businessmen. The study summarizes the methods, tools and means of state regulation in the monetary sphere in order to strengthen the financial security of the state. The conceptual basis for the formation and implementation of monetary policy has been developed. The authors conclude that the strategic vector of movement for Ukraine is the need to adopt a specialized legislative act "On cryptocurrency circulation in Ukraine" in order to create conditions for the introduction of network segmentation technologies, which in the long run will reduce globalization and further develop cryptocurrency market infrastructure.
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Wright, Keith. "The Case for a Technology Solution to the Ethics Crisis in Academic Publishing." International Journal of Technoethics 12, no. 1 (2021): 1–20. http://dx.doi.org/10.4018/ijt.2021010101.
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This article integrates existing theory from distributed computing and cryptology with gray literature from industry to provide a comprehensive description of the minimum requirements of a technological solution to the current ethics crisis in academic publishing. The paper argues that such a solution could significantly reduce the biases and misconduct that now exist in the academic peer review process. Theory suggests such a system could operate effectively as a distributed encrypted telecommunications network where nodes are anonymous, do not trust each other, with minimal central authority. To incentivize the academic community to join such a community, the paper proposes a new pseudo-cryptocurrency called litcoin (literature coin). This litcoin-based system would create economic scarcity based on proof of knowledge (POK), which is a synthesis of the proof of work (POW) mechanism used in bitcoin, and the proof of stake (POS) mechanism used in various altcoin communities.
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Momoh, Muyideen Omuya, P. U. Chinedu, W. Nwankwo, D. Aliu, and M. S. Shaba. "BLOCKCHAIN ADOPTION: APPLICATIONS AND CHALLENGES." International Journal of Software Engineering and Computer Systems 7, no. 2 (2021): 19–25. http://dx.doi.org/10.15282/ijsecs.7.2.2021.3.0086.
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In recent times, more scholastic and social attention have been paid to blockchain and its distributed ledger system mechanism. The reasons for this ever-increasing attention cannot be far-fetched: blockchain now occupies a copious position in the present-day ways of doing things economically, digitally and ‘digital-socially’. Blockchain could be described as a distributed ledger system that allows secure transactions without a central management system. In this distributed ledger system, transactions are coded into blocks, which are linked to each other in the form of a chain. The first application of blockchain is in the bitcoin cryptocurrency. Though not limited to bitcoin, blockchain finds usefulness in security and trusts for instance, digital assets could be coded into blocks to ensure and enforce quality of trust. Consequent upon the quality of trust the blockchain confers on a digital asset, transparency among participating nodes is guaranteed. This is because, any change made to any record in a given block automatically initiates and enforces a corresponding change in all other blocks in the chain hence tampering or breach is almost impossible. Owing to its impressive prospects in the socioeconomic and political ecosystem, this paper was conceived to examine the current developments around this novel technology with particular emphasis on its benefits and proposed challenges and needs to fill the gap created in the vital socioeconomic domains. The paper concludes that the blockchain technology is a plausible approach to restoring the trust, confidentiality, availability and integrity in transactions in the cyberspace and the world at large as majority of the global economy thrives in the cloud.
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Christodoulou, Klitos, Elias Iosif, Antonios Inglezakis, and Marinos Themistocleous. "Consensus Crash Testing: Exploring Ripple’s Decentralization Degree in Adversarial Environments." Future Internet 12, no. 3 (2020): 53. http://dx.doi.org/10.3390/fi12030053.
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The inception of Bitcoin as a peer-to-peer payment system, and its underlying blockchain data-structure and protocol, has led to an increased interest in deploying scalable and reliable distributed-ledger systems that build on robust consensus protocols. A critical requirement of such systems is to provide enough fault tolerance in the presence of adversarial attacks or network faults. This is essential to guarantee liveness when the network does not behave as expected and ensure that the underlying nodes agree on a unique order of transactions over a shared state. In comparison with traditional distributed systems, the deployment of a distributed-ledger system should take into account the hidden game theoretical aspects of such protocols, where actors are competing with each other in an environment which is likely to experience various well-motivated malicious and adversarial attacks. Firstly, this paper discusses the fundamental principles of existing consensus protocols in the context of both permissioned and permissionless distributed-ledger systems. The main contribution of this work deals with observations from experimenting with Ripple’s consensus protocol as it is embodied in the XRP Ledger. The main experimental finding suggests that, when a low percentage of malicious nodes is present, the centralization degree of the network can be significantly relaxed ensuring low convergence times. Those findings are of particular importance when engineering a consensus algorithm that would like to balance security with decentralization.
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Lundbæk, Leif-Nissen, Daniel Janes Beutel, Michael Huth, Stephen Jackson, Laurence Kirk, and Robert Steiner. "Proof of Kernel Work: a democratic low-energy consensus for distributed access-control protocols." Royal Society Open Science 5, no. 8 (2018): 180422. http://dx.doi.org/10.1098/rsos.180422.
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We adjust the Proof of Work (PoW) consensus mechanism used in Bitcoin and Ethereum so that we can build on its strength while also addressing, in part, some of its perceived weaknesses. Notably, our work is motivated by the high energy consumption for mining PoW, and we want to restrict the use of PoW to a configurable, expected size of nodes, as a function of the local blockchain state. The approach we develop for this rests on three pillars: (i) Proof of Kernel Work (PoKW), a means of dynamically reducing the set of nodes that can participate in the solving of PoW puzzles such that an adversary cannot increase his attack surface because of such a reduction; (ii) Practical Adaptation of Existing Technology , a realization of this PoW reduction through an adaptation of existing blockchain and enterprise technology stacks; and (iii) Machine Learning for Adaptive System Resiliency , the use of techniques from artificial intelligence to make our approach adaptive to system, network and attack dynamics. We develop here, in detail, the first pillar and illustrate the second pillar through a real use case, a pilot project done with Porsche on controlling permissions to vehicle and data log accesses. We also discuss pertinent attack vectors for PoKW consensus and their mitigation. Moreover, we sketch how our approach may lead to more democratic PoKW-based blockchain systems for public networks that may inherit the resilience of blockchains based on PoW.
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Sabri-Laghaie, Kamyar, Saeid Jafarzadeh Ghoushchi, Fatemeh Elhambakhsh, and Abbas Mardani. "Monitoring Blockchain Cryptocurrency Transactions to Improve the Trustworthiness of the Fourth Industrial Revolution (Industry 4.0)." Algorithms 13, no. 12 (2020): 312. http://dx.doi.org/10.3390/a13120312.
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A completely new economic system is required for the era of Industry 4.0. Blockchain technology and blockchain cryptocurrencies are the best means to confront this new trustless economy. Millions of smart devices are able to complete transparent financial transactions via blockchain technology and its related cryptocurrencies. However, via blockchain technology, internet-connected devices may be hacked to mine cryptocurrencies. In this regard, monitoring the network of these blockchain-based transactions can be very useful to detect the abnormal behavior of users of these cryptocurrencies. Therefore, the trustworthiness of the transactions can be assured. In this paper, a novel procedure is proposed to monitor the network of blockchain cryptocurrency transactions. To do so, a hidden Markov multi-linear tensor model (HMTM) is utilized to model the transactions among nodes of the blockchain network. Then, a multivariate exponentially weighted moving average (MEWMA) control chart is applied to the monitoring of the latent effects. Average run length (ARL) is used to evaluate the performance of the MEWMA control chart in detecting blockchain network anomalies. The proposed procedure is applied to a real dataset of Bitcoin transactions.
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Tapas, Nachiket, Yechiav Yitzchak, Francesco Longo, Antonio Puliafito, and Asaf Shabtai. "P4UIoT: Pay-Per-Piece Patch Update Delivery for IoT Using Gradual Release." Sensors 20, no. 7 (2020): 2156. http://dx.doi.org/10.3390/s20072156.
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P 4 UIoT—pay-per-piece patch update delivery for IoT using gradual release—introduces a distributed framework for delivering patch updates to IoT devices. The framework facilitates distribution via peer-to-peer delivery networks and incentivizes the distribution operation. The peer-to-peer delivery network reduces load by delegating the patch distribution to the nodes of the network, thereby protecting against a single point of failure and reducing costs. Distributed file-sharing solutions currently available in the literature are limited to sharing popular files among peers. In contrast, the proposed protocol incentivizes peers to distribute patch updates, which might be relevant only to IoT devices, using a blockchain-based lightning network. A manufacturer/owner named vendor of the IoT device commits a bid on the blockchain, which can be publicly verified by the members of the network. The nodes, called distributors, interested in delivering the patch update, compete among each other to exchange a piece of patch update with cryptocurrency payment. The pay-per-piece payments protocol addresses the problem of misbehavior between IoT devices and distributors as either of them may try to take advantage of the other. The pay-per-piece protocol is a form of a gradual release of a commodity like a patch update, where the commodity can be divided into small pieces and exchanged between the sender and the receiver building trust at each step as the transactions progress into rounds. The permissionless nature of the framework enables the proposal to scale as it incentivizes the participation of individual distributors. Thus, compared to the previous solutions, the proposed framework can scale better without any overhead and with reduced costs. A combination of the Bitcoin lightning network for cryptocurrency incentives with the BitTorrent delivery network is used to present a prototype of the proposed framework. Finally, a financial and scalability evaluation of the proposed framework is presented.
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Zhou, Wei. "Fuzzy rules based efficient event-driven simulation of blockchain-based applications." Journal of Intelligent & Fuzzy Systems 40, no. 4 (2021): 8101–7. http://dx.doi.org/10.3233/jifs-189633.
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Decentralized application (DAPP), replacing traditional business logic and data access layer with block chain, is a new form of Internet service. Testing DAPP requires large-scale distributed systems. Performing experiments in a real system is costly and difficult. This article carefully analyses the process of block generation and synchronization and explains the reasons for the low efficiency of block chain system simulation. We incorporate fuzzy rule based model for enhancing the logging system in blockchain. Rules based on fuzzy are utilized inside system of fuzzy logic to obtain outcome on basis of input variables. The data of Ethereum and Bitcoin proves that the block generation interval conforms to the exponential distribution, and the real PoW calculation can be replaced with random numbers. Both block verification and network propagation processes have latency, which can be simulated with asynchronous messaging. Based on the above analysis, this article proposes a high-performance simulation method based on event-driven model, which is suitable for describing the communication and synchronization behave our of block chain networks. The method can effectively describe the block generation, the synchronization process between nodes, and supports different equity proof forms. Using this method, the performance of the PoW systemis tested. Under the ecs.c6.xlargeinstance,the simulation running speed reaches 782 times of actual system. Further experiments show that this method can be efficiently used in larger-scale networks and is an effective tool for DAPP developing and testing.
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Huntley, Dave. "Detecting a security breach and pinpointing its source." International Symposium on Microelectronics 2020, no. 1 (2020): 000067–72. http://dx.doi.org/10.4071/2380-4505-2020.1.000067.
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Abstract There are many rapidly emerging technologies to embed a “Root of Trust” (RoT) in silicon or in assembled packages and PCBs further down the supply chain. These all aim to provide an un-hackable proof of device identity and uncompromised firmware. Despite these efforts we can, and should, assume that bad actors will succeed to counterfeit devices, install malware, etc. So how do we detect and respond to these attacks in time before they cause too much harm? This is, of course, of particular concern for defense and aerospace applications. We will discuss an initiative at SEMI to provide asset traceability through the supply chain. The intention is to detect counterfeits and security attacks quickly, track them back through the supply chain and identify the culprit. The threat of capture and penalties is expected to reduce the incentive for the bad actors in future. The proposed SEMI standard will define the transactions and data required to record chain of custody for electronic assets as they flow through the supply chain. These transactions will be recorded on Hyperledger Fabric, a blockchain platform which offers an immutable transaction ledger, maintained within a distributed network of peer nodes. The ledger will not be public (like bitcoin), nor will it be private to one organization. Instead it will follow a consortium model and be permissioned to support flexible trust assumptions. The SEMI standard will facilitate supply chain members to form one or more consortiums and host the Hyperledger nodes. This will enable the early detection and response to counterfeit and security threats to electronic assets that the supply chain members manufacture or distribute. The standard takes care not to expose any confidential technical or commercial information. However, Hyperledger offers the concepts of private data collections and channels to allow for the sharing of private data between specific members. This could become an enabler to realize the data sharing required to meet Smart Manufacturing 4.0 objectives. There are a number of similar chain of custody ledger initiatives underway both in the commercial and standards arena. The hope is that the SEMI standard will encourage these systems to merge into an industry wide consortium with increased interoperability, performance, reliability and security.
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Baldominos, Alejandro, and Yago Saez. "Coin.AI: A Proof-of-Useful-Work Scheme for Blockchain-Based Distributed Deep Learning." Entropy 21, no. 8 (2019): 723. http://dx.doi.org/10.3390/e21080723.
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One decade ago, Bitcoin was introduced, becoming the first cryptocurrency and establishing the concept of “blockchain” as a distributed ledger. As of today, there are many different implementations of cryptocurrencies working over a blockchain, with different approaches and philosophies. However, many of them share one common feature: they require proof-of-work to support the generation of blocks (mining) and, eventually, the generation of money. This proof-of-work scheme often consists in the resolution of a cryptography problem, most commonly breaking a hash value, which can only be achieved through brute-force. The main drawback of proof-of-work is that it requires ridiculously large amounts of energy which do not have any useful outcome beyond supporting the currency. In this paper, we present a theoretical proposal that introduces a proof-of-useful-work scheme to support a cryptocurrency running over a blockchain, which we named Coin.AI. In this system, the mining scheme requires training deep learning models, and a block is only mined when the performance of such model exceeds a threshold. The distributed system allows for nodes to verify the models delivered by miners in an easy way (certainly much more efficiently than the mining process itself), determining when a block is to be generated. Additionally, this paper presents a proof-of-storage scheme for rewarding users that provide storage for the deep learning models, as well as a theoretical dissertation on how the mechanics of the system could be articulated with the ultimate goal of democratizing access to artificial intelligence.
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"An Effective Randomization Framework to POW Consensus Algorithm of Blockchain (RPoW)." International Journal of Engineering and Advanced Technology 8, no. 6 (2019): 1793–97. http://dx.doi.org/10.35940/ijeat.f8456.088619.
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Blockchain technology has become a buzzword due to its intuitive applications and its decentralized network architecture. Blockchain is a decentralized system that uses peer -to - peer networking and appropriate consensus algorithm for secure and reliable transactions and records them all in an immutable ledger as chain of blocks. The world got introduced to the blockchain technology, when Satoshi Nakamoto released Bitcoin in 2009[2]. Though this technology is famous for being the backbone of cryptocurrencies, it has got into various industry domains and many applications have been developed using blockchain [11]. The consensus algorithm used in Blockchain architecture influences how agreement is made to add a new block among all the nodes in the network. PoW (Proof of work) is the consensus algorithm applied in the Bitcoin network architecture and many other blockchain applications. PoW requires each node to solve a cryptographic puzzle with adjusted difficulty, to get the privilege to add a new block to the current chain. The first node that solves the puzzle will have this privilege and some reward. Proof-of-Work (PoW) uses extensive amounts of electric power and steep computing hardware as an effect of their consensus procedure [1]. This proposed work presents an effective randomization framework that reduces the execution time required to calculate the hash value. The number of instruction-set required to compute the PoW consensus is also reduced. This approach helps in maintaining a fair decentralized network to construct blockchain applications.
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Mhana, Ammar, Ghassan N. Mohammed, and Fadhel K. Jabor. "Enhancing Privacy and Improving Security in Scalable Blockchain." Journal of Southwest Jiaotong University 54, no. 5 (2019). http://dx.doi.org/10.35741/issn.0258-2724.54.5.7.
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Bitcoin is a decentralized blockchain-based cryptocurrency that has taken the world by storm. Since its introduction in 2009, it has grown tremendously in terms of popularity and market cap. The idea of having a decentralized public ledger while maintaining anonymity and security attracted the attention of developers and customers alike. Special nodes in the bitcoin network, called miners, are responsible for making the network secure by using a concept called proof-of-work. A certain degree of anonymity is also maintained as no personally identifiable information of a person, like name, address, etc., is linked to the bitcoin wallet. In terms of bitcoin, a user is anonymous if different interactions of the user cannot be linked to each other or the user. Recent research shows that bitcoin is not as anonymous as it appears to be. The inherently public nature of blockchain technology makes it difficult to achieve privacy. The purpose of this paper is to review how varying degrees of user privacy is maintained in bitcoin cryptocurrency. This paper is divided into two main segments. The first segment explores privacy-enhancing techniques adopted in bitcoin. The second segment critically analyzes these techniques.
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"Preventing the Bitcoin Double Spend using Transaction Hash and Unspent Transaction Output." International Journal of Recent Technology and Engineering 8, no. 3 (2019): 3771–76. http://dx.doi.org/10.35940/ijrte.c5352.098319.
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The red-hot crypto currency is a bitcoin which occupies first position in the capital investment of financial world which is assaulted by various factors like wallet attacks, network attacks, mining attacks and double spending attacks. Double spending is the major attack in which the attacker tries to cheat the network nodes and use the same coin for more than one set of transactions. Of this the original transaction identification from the set of transactions is a challenging one. In this paper we propose a solution for identifying the primary transaction from the set of double spended or multi spended transactions. The proposed approach finds the authentic transaction from the list of double spended transactions using transaction hash value, which is primarily used for every transaction in the Bitcoin network. Transaction hash value is used as transaction identifier for each bitcoin transaction. By comparing the transaction hash value with the existing pool of unconfirmed input pool, transhash pool and utxopool one can identify the genuine transaction from the flawed transaction list. The firsthand transaction is then added to the Confirmed input pool which is then entered into the newly added block of the blockchain. This architecture will prevent the double spend of bitcoin further in the network which facilitates the network nodes as well as minimize the miners task for verification and validation of transaction.
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Pathak, Prof Mrunal, Amol Suradkar, Ajinkya Kadam, Akansha Ghodeswar, and Prashant Parde. "Blockchain Based E-Voting System." International Journal of Scientific Research in Science and Technology, May 5, 2021, 134–40. http://dx.doi.org/10.32628/ijsrst2182120.
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Increasingly digital technology in the present helped many people lives. Unlike the electoral system, there are many conventional uses of paper in its implementation. The aspect of security and transparency is a threat from still widespread election with the conventional system (offline). General elections still use a centralized system, there is one organization that manages it. Some of the problems that can occur in traditional electoral systems is with an organization that has full control over the database and system, it is possible to tamper with the database of considerable opportunities. Blockchain technology is one of solutions, because it embraces a decentralized system and the entire database are owned by many users. Blockchain itself has been used in the Bitcoin system known as the decentralized Bank system. By adopting blockchain in the distribution of databases on e-voting systems can reduce one of the cheating sources of database manipulation. This research discusses the recording of voting result using blockchain algorithm from every place of election. Unlike Bitcoin with its Proof of Work, this thesis proposed a method based on a predetermined turn on the system for each node in the built of blockchain
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Zhou, Lu, Chunpeng Ge, and Chunhua Su. "A privacy preserving two-factor authentication protocol for the Bitcoin SPV nodes." Science China Information Sciences 63, no. 3 (2020). http://dx.doi.org/10.1007/s11432-019-9922-x.
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Motamed, Amir Pasha, and Behnam Bahrak. "Quantitative analysis of cryptocurrencies transaction graph." Applied Network Science 4, no. 1 (2019). http://dx.doi.org/10.1007/s41109-019-0249-6.
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AbstractCryptocurrencies as a new way of transferring assets and securing financial transactions have gained popularity in recent years. Transactions in cryptocurrencies are publicly available, hence, statistical studies on different aspects of these currencies are possible. However, previous statistical analysis on cryptocurrencies transactions have been very limited and mostly devoted to Bitcoin, with no comprehensive comparison between these currencies. In this study, we intend to compare the transaction graph of Bitcoin, Ethereum, Litecoin, Dash, and Z-Cash, with respect to the dynamics of their transaction graphs over time, and discuss their properties. In particular, we observed that the growth rate of the nodes and edges of the transaction graphs, and the density of these graphs, are closely related to the price of these currencies. We also found that the transaction graph of these currencies is non-assortative, i.e. addresses do not tend for transact with a particular type of addresses of higher or lower degree, and the degree sequence of their transaction graph follows the power law distribution.
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Fischer, Jan Alexander, Andres Palechor, Daniele Dell’Aglio, Abraham Bernstein, and Claudio J. Tessone. "The Complex Community Structure of the Bitcoin Address Correspondence Network." Frontiers in Physics 9 (June 30, 2021). http://dx.doi.org/10.3389/fphy.2021.681798.
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Bitcoin is built on a blockchain, an immutable decentralized ledger that allows entities (users) to exchange Bitcoins in a pseudonymous manner. Bitcoins are associated with alpha-numeric addresses and are transferred via transactions. Each transaction is composed of a set of input addresses (associated with unspent outputs received from previous transactions) and a set of output addresses (to which Bitcoins are transferred). Despite Bitcoin was designed with anonymity in mind, different heuristic approaches exist to detect which addresses in a specific transaction belong to the same entity. By applying these heuristics, we build an Address Correspondence Network: in this representation, addresses are nodes are connected with edges if at least one heuristic detects them as belonging to the same entity. In this paper, we analyze for the first time the Address Correspondence Network and show it is characterized by a complex topology, signaled by a broad, skewed degree distribution and a power-law component size distribution. Using a large-scale dataset of addresses for which the controlling entities are known, we show that a combination of external data coupled with standard community detection algorithms can reliably identify entities. The complex nature of the Address Correspondence Network reveals that usage patterns of individual entities create statistical regularities; and that these regularities can be leveraged to more accurately identify entities and gain a deeper understanding of the Bitcoin economy as a whole.
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"Discovering the Bitcoin Double Spend using Lost Agreement Amount." International Journal of Recent Technology and Engineering 8, no. 3 (2019): 3764–70. http://dx.doi.org/10.35940/ijrte.c5351.098319.
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In the modernized world like digital world, traditional way of payments through banks and other third parties are out of sphere. To meet the digital competency digital token like bitcoin based crypto currency payment is required. Lots of business persons are moving towards the digital way of secure payment. Intruders like hackers hamper the digital token and make immortality in the transaction which in turn create the double spend. Double spend is a serious threat in the Bitcoin network. Our research work focuses on double spend detection of transaction before it gets confirmed and added to the block by the miners. The proposed new architecture for detecting double spend using Dual Payout based on Lost Agreement Amount (DPL2A) will identify one of the ways that double spend attack occur before it is added to the blockchain. This architecture gives the clear identification of double spend attack and their full details of transaction occurrence so that when it is broadcasted into the peer-to-peer network, the network nodes will use this architecture to detect double spend, its occurrence is fully prevented and only the genuine transaction will be added to the blockchain.
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Shinde, Chetan, Atharav Upare, Vishal Pawar, and Ajay Raut. "Decentralized Stock and Cryptocurrency Exchange." International Journal of Advanced Research in Science, Communication and Technology, April 6, 2021, 63–68. http://dx.doi.org/10.48175/ijarsct-937.
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We propose a new blockchain-based framework for a completely decentralized stock market and bitcoin exchange in this paper. By proposing a groundbreaking framework utilizing blockchain to build a decentralized bitcoin and stock exchange network, this paper discusses the shortcomings of conventional centralized stock exchange platforms, High transaction costs, vulnerable centralized governance, and a lack of clarity in consumer behavior and algorithms are just a few of the problems. Blockchain technology consists of a large number of computer nodes that share a shared ledger securely without the need for intermediaries of any sort. The proposed blockchain-based solution addresses the disadvantages of the centralized stock exchange architecture by ensuring the integrity and security of the properties and orders of the owner, by self-enforcing intelligent agreements between parties, and by consensus algorithms, by achieving democratic and effective decisions on the execution and settlement of orders. Intelligent contracts are used in the proposed architecture to enforce the validation of the owner's rights as well as the proper execution and settlement of orders, reducing the need for a central authority to ensure that the stock exchange process is accurate. The proposed system proposes a hybrid platform that incorporates cryptocurrency and stock trading. The solution was tested for a subset of rules for the Stock Exchange by implementing a prototype in Ethereum.
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Polat, Onur, and Eylül Kabakçı Günay. "Cryptocurrency connectedness nexus the COVID-19 pandemic: evidence from time-frequency domains." Studies in Economics and Finance ahead-of-print, ahead-of-print (2021). http://dx.doi.org/10.1108/sef-01-2021-0011.
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Purpose The purpose of this study is to investigate volatility connectedness between major cryptocurrencies by the virtue of market capitalization. In this context, this paper implements the frequency connectedness approach of Barunik and Krehlik (2018) and to measure short-, medium- and long-term connectedness between realized volatilities of cryptocurrencies. Additionally, this paper analyzes network graphs of directional TO/FROM spillovers before and after the announcement of the COVID-19 pandemic by the World Health Organization. Design/methodology/approach In this study, we examine the volatility connectedness among eight major cryptocurrencies by the virtue of market capitalization by using the frequency connectedness approach over the period July 26, 2017 and October 28, 2020. To this end, this paper computes short-, medium- and long-cycle overall spillover indexes on different frequency bands. All indexes properly capture well-known events such as the 2018 cryptocurrency market crash and COVID-19 pandemic and markedly surge around these incidents. Furthermore, owing to notably increased volatilities after the official announcement of the COVID-19 pandemic, this paper concentrates on network connectedness of volatility spillovers for two distinct periods, July 26, 2017–March 10, 2020 and March 11, 2020–October 28, 2020, respectively. In line with the related studies, major cryptocurrencies stand at the epicenter of the connectedness network and directional volatility spillovers dramatically intensify based on the network analysis. Findings Overall spillover indexes have fluctuated between 54% and 92% in May 2018 and April 2020. The indexes gradually escalated till November 9, 2018 and surpassed their average values (71.92%, 73.66% and 74.23%, respectively). Overall spillover indexes dramatically plummeted till January 2019 and reached their troughs (54.04%, 57.81% and 57.81%, respectively). Etherium catalyst the highest sum of volatility spillovers to other cryptocurrencies (94.2%) and is followed by Litecoin (79.8%) and Bitcoin (76.4%) before the COVID-19 announcement, whereas Litecoin becomes the largest transmitter of total volatility (89.5%) and followed by Bitcoin (89.3%) and Etherium (88.9%). Except for Etherium, the magnitudes of total volatility spillovers from each cryptocurrency notably increase after – COVID-19 announcement period. The medium-cycle network topology of pairwise spillovers indicates that the largest transmitter of total volatility spillover is Litecoin (89.5%) and followed by Bitcoin (89.3%) and Etherium (88.9%) before the COVID-19 announcement. Etherium keeps its leading role of transmitting the highest sum of volatility spillovers (89.4%), followed by Bitcoin (88.9%) and Litecoin (88.2%) after the COVID-19 announcement. The largest transmitter of total volatility spillovers is Etherium (95.7%), followed by Litecoin (81.2%) and Binance Coin (75.5%) for the long-cycle connectedness network in the before-COVID-19 announcement period. These nodes keep their leading roles in propagating volatility spillover in the latter period with the following sum of spillovers (Etherium-89.5%, Bitcoin-88.9% and Litecoin-88.1%, respectively). Research limitations/implications The study can be extended by including more cryptocurrencies and high-frequency data. Originality/value The study is original and contributes to the extant literature threefold. First, this paper identifies connectedness between major cryptocurrencies on different frequency bands by using a novel methodology. Second, this paper estimates volatility connectedness between major cryptocurrencies before and after the announcement of the COVID-19 pandemic and thereby to concentrate on its impact on the cryptocurrency market. Third, this paper plots network graphs of volatility connectedness and herewith picture the intensification of cryptocurrencies due to a major financial distress event.