Abstract Visibility of digital art and its ownership can be achieved using blockchain technology as part of a broader solution for the identification, attribution, and payment for digital work. A case study is provided of a firm using the Bitcoin blockchain as part of an integrated solution to identify and authenticate ownership of digital property. An integrated ownership ledger allows for secure attribution, transfer, and provenance of digital property. Blockchain technology enables limited‐edition digital property, while Internet‐scale web crawl and machine learning shows where and how works are being used on the Internet.
A blockchain is a public ledger for recording transactions, maintained by<br> many nodes without central authority through a distributed cryptographic<br> protocol. All nodes validate the information to be appended to the<br> blockchain, and a consensus protocol ensures that the nodes agree on a<br> unique order in which entries are appended. Consensus protocols for<br> tolerating Byzantine faults have received renewed attention because they<br> also address blockchain systems. However, amid the current hype around<br> blockchains, cryptocurrencies, fintech startups, and novel consensus<br> mechanisms, it is sometimes overlooked that assessing and gaining<br> confidence in the resilience of a protocol is a difficult task. We argue that developing consensus protocols is similar to engineering<br> cryptographic systems, and that blockchain developers should look towards<br> the established experience in cryptography and security with building<br> trustworthy systems. Otherwise, it might be dangerous to entrust<br> financial value to new protocols. Public discussion, expert reviews,<br> broad validation, and standards recommendations should be employed,<br> following the established practice in cryptography and security.<br>
Richard Adams, Glenn Parry, Phil Godsiff, Peter M. Ward
Abstract Blockchain technology provides an exciting application space for innovation in diverse domains but threatens disintermediation for organizations providing a trusted and auditable account of ownership and transactions. It needs, however, an appropriate regulation to keep pace with technological developments. Technology remains very young, akin to the Internet in the early 1990s. Use cases, practical demonstrators, standards, and lexical consistency are urgently required.
Abstract—As data is having an increasingly relevant role<br> in dierent business fields, ensuring integrity has become<br> fundamental. Modern databases rely on transaction history<br> written on redo logs to allow for data restore. However, if<br> redo logs are (maliciously) forged, data can actually be lost or<br> altered. Due its strong data integrity guarantees, blockchain<br> technology can be employed to ensure log integrity, but its<br> current performance limitations hinder actual exploitations.<br> In previous work, we proposed a layered blockchain-based<br> architecture for distributed (federated) database redo logs: a<br> fast first layer blockchain, anchored to a secure second layer<br> blockchain, based on proof-of-work to achieve strong integrity.<br> Here, we present an implementation and an experimental<br> evaluation of a prototype of that architecture, which employs a<br> total consensus algorithm on the first layer blockchain. Finally,<br> to improve availability and scalability, we refine our solution<br> by investigating, respectively, a Byzantine Fault Tolerant consensus<br> and a Distributed Hash Table solution to shard the first<br> layer blockchain ledger among available nodes.
Abstract Cryptocurrencies and blockchain technology are playing an increasingly important role for organizations that seek to build social and solidarity‐based finance. Blockchain technology has emerged as a potential disruptor for the financial industry. However, cryptocurrencies and blockchain technology may help develop organizations that seek to build social and solidarity‐based finance.
After more than eight years since the launch of Bitcoin, the decentralized transaction ledger functionality implemented through the blockchain technology is being used not only for cryptocurrencies, but to register, confirm and transfer any kind of contract and property. In this work, we analyze the most relevant functionalities and known issues of this technology, with the intent of pointing out the possible behaviours that are not as efficient and reliable as they should be when thinking with a broader outlook.
Open access
Blockchain Technology Applications and Security
Cryptography and Data Security
Advanced Steganography and Watermarking Techniques
This paper presents a simple game theoretic framework, assuming complete information, to model Bitcoin mining activity. It does so by formalizing the activity as an all-pay contest: a competition where participants contend with each other to win a prize by investing in computational power, and victory is probabilistic. With at least two active miners, the unique pure strategy Nash equilibrium of the game suggests the following interesting insights on the motivation for being a miner: while the optimal amount of energy consumption depends also on the reward for solving the puzzle, as long as the reward is positive the decision to be an active miner depends only on the mining costs. Moreover, the intrinsic structure of the mining activity seems to prevent the formation of a monopoly, because in an equilibrium with two miners, both of them will have positive expected profits for any level of the opponent’s costs. A monopoly could only form if the rate of return on investment were higher outside bitcoin.
Abstract The blockchain innovation appears to represent viable catalysts for achieving global sustainable development targets. Projects and initiatives seeking to extend the reach of distributed ledger technologies (DLTs) seem mostly intended for the benefit of for‐profit businesses, governments, and consumers. DLT projects devised for the public good could aim, in theory, to fulfill the United Nation’s current sustainable development goals. Blockchain technology is being applied in ways that could transform this ambition for good into a practical reality.
Bitcoin has advanced as the most fruitful cryptographic currency in history. Since its launch in 2009.Bitcoingrewtocomprisebillionsofdollarsofecono mic value. Since then a lot of literature has been identified with concealed-but-vital properties of the system, exposed attacks, proposed promising alternatives, and singled out dif challenges. This paper threw light to many related cryptocurrencies or 'altcoins' and enables a more insightful analysis of Bitcoin's properties. The researcher maps the space for providing analyses for bitcoin mining, bitcoin protocol, and bitcoin value determinations.This paper surveys the anonymity in Bitcoins and provides an insight into the framework for analysing the mining hardware, the calculation of Bitcoin value by reviewing various literatures and websites related to Bitcoins.
Bitcoin is the world's first completely decentralized peer-to-peer digital currency. The main reason behind using bitcoin is that of its low transaction fee compared to any other transfers like western union, credit card transaction etc. and bitcoin transactions are transparent. So we don't have to consider about tax problems.It avoids Taxation.
Yu‐Jin Kwon, Do-Hyun Kim, Yunmok Son, Eugene Y. Vasserman · 5 authors
In the Bitcoin system, participants are rewarded for solving cryptographic puzzles. In order to receive more consistent rewards over time, some participants organize mining pools and split the rewards from the pool in proportion to each participant's contribution. However, several attacks threaten the ability to participate in pools. The block withholding (BWH) attack makes the pool reward system unfair by letting malicious participants receive unearned wages while only pretending to contribute work. When two pools launch BWH attacks against each other, they encounter the miner's dilemma: in a Nash equilibrium, the revenue of both pools is diminished. In another attack called selfish mining, an attacker can unfairly earn extra rewards by deliberately generating forks. In this paper, we propose a novel attack called a fork after withholding (FAW) attack. FAW is not just another attack. The reward for an FAW attacker is always equal to or greater than that for a BWH attacker, and it is usable up to four times more often per pool than in BWH attack. When considering multiple pools - the current state of the Bitcoin network - the extra reward for an FAW attack is about 56% more than that for a BWH attack. Furthermore, when two pools execute FAW attacks on each other, the miner's dilemma may not hold: under certain circumstances, the larger pool can consistently win. More importantly, an FAW attack, while using intentional forks, does not suffer from practicality issues, unlike selfish mining. We also discuss partial countermeasures against the FAW attack, but finding a cheap and efficient countermeasure remains an open problem. As a result, we expect to see FAW attacks among mining pools.
Ekosistem Internet of Things (IoT) berkembang dengan sangat cepat dan diperkirakan akan menghubungkan 5-20 miliar perangkat pada tahun 2020. Data yang dihimpun dari perangkat ini akan mencapai jumlah yang sangat besar. Saat ini, ekosistem IoT pada umumnya menggunakan model sistem terpusat. Model tersebut memiliki beberapa kelemahan, seperti biaya pemeliharaan yang relatif tinggi, Sistem terdistribusi dapat menjadi alternatif solusi. Blockchain, teknologi ledger terditribusi, memungkinkan transaksi peer-to-peer tanpa perlu adanya perantara pihak ketiga yang terpercaya. Paper ini bertujuan untuk mengeksplorasi potensi pengintegrasian Blockchain ke dalam ekosistem IoT. Hasil penelitian berupa model dan use-case pemanfaatan Blockchain dalam IoT.
Colin Andrews, Daniel Broby, Greig Paul, Robert Ian Whitfield
In this paper, blockchain is explored from the perspective of what can been learnt from research conducted in financial markets. It is concluded that the digital aspirations of what has come to be termed “Industry 4.0” could be enhanced by the application of blockchains in advanced manufacturing. Our core finding is that blockchain can be used to provide advanced manufacturers with secure ownership verification, parts and order validation. We have learnt from financial applications that blockchain can offer a robust and resilient method of record history indexing that can be distributed and stored over the internet. We advise, however, that It is not as scalable a storage tool, as is widely perceived. Stored information must be carefully considered by manufacturers. We suggest that it is its data management capabilities that make it useful in the advanced manufacturing.
The blockchain is a peer to peer technology that protects the integrity of a digital piece of information. It can serve as a digital decentralized distributed ledger that can record sharing of information between two parties in a permanent way. All the information is stored in a network of personal computers. Each computer has memory records called blocks and each block has a time stamp and a link to the previous block as a hash pointer. All the records are secured using cryptography. Timestamp keeps the track of creation of the record. Once the record is created no one can manipulate the records, not even the owner. It keeps the proof and exact time at which that data exists. A hash function is a mathematical algorithm and algorithm is made is in such a way that is it a one-way function that means the process cannot be rolled back. Next generation of the Internet will be using in FITS.
Carlos Oliver, Alessandro Ricottone, Pericles Philippopoulos
We propose a proof-of-work algorithm that rewards blockchain miners for using computational resources to solve NP-complete puzzles. The resulting blockchain will publicly store and improve solutions to problems with real world applications while maintaining a secure and fully functional transaction ledger.
An appealing feature of blockchain technology is smart contracts. A smart contract is executable code that runs on top of the blockchain to facilitate, execute and enforce an agreement between untrusted parties without the involvement of a trusted third party. In this paper, we conduct a systematic mapping study to collect all research that is relevant to smart contracts from a technical perspective. The aim of doing so is to identify current research topics and open challenges for future studies in smart contract research. We extract 24 papers from different scientific databases. The results show that about two thirds of the papers focus on identifying and tackling smart contract issues. Four key issues are identified, namely, codifying, security, privacy and performance issues. The rest of the papers focuses on smart contract applications or other smart contract related topics. Research gaps that need to be addressed in future studies are provided.
Since its inception, the blockchain technology has shown promising application prospects. From the initial cryptocurrency to the current smart contract, blockchain has been applied to many fields. Although there are some studies on the security and privacy issues of blockchain, there lacks a systematic examination on the security of blockchain systems. In this paper, we conduct a systematic study on the security threats to blockchain and survey the corresponding real attacks by examining popular blockchain systems. We also review the security enhancement solutions for blockchain, which could be used in the development of various blockchain systems, and suggest some future directions to stir research efforts into this area.
Open access
4 source records
Blockchain Technology Applications and Security
Advanced Steganography and Watermarking Techniques
Over eight years from its conception, Blockchain is considered as a ground-breaking innovation in information technology. The technology’s promises of complete disintermediation and enhanced process visibility turned supply chain and logistics into a fertile ground for a blockchain potential implementation. Despite these high expectations, both practitioners and researchers still struggle in identifying the blockchain real benefits to the industry. Moreover, the several private projects and start-ups offering blockchain solutions, which are blossoming in the logistics environment, are threatening the role of the Port of Rotterdam and Portbase as the port inter-organizational information system. Commissioned by Smartport, this research aims to identify the potential blockchain uses on port logistics as well as their relative impact. Therefore, the functionality offered by the current market applications are categorized into four business cases, which identify different uses of the blockchain. These blockchain business cases are subsequently analyzed under six different points of view in order to evaluate the expected benefit that the major stakeholder expect to gain from the technology implementation. Finally, the impact of these business cases is tested on the business model components of the current port information system, Portbase, to identify the disruptive power of the technology. To face the potential issue of disintermediation; a set of solutions have been developed for Portbase on how to adapt its business model in case of a blockchain implementation. This strong conceptualization of the blockchain technology helps the main logistic stakeholders to understand and discuss the potential application of blockchain technology on port logistics, and it provides a much-needed basis for further scientific research. Further development of this conceptualization is needed to structure the ongoing blockchain discussions in both scientific literature and practice.
Anand Kumar Mishra, Shrikant Tiwari, Kanchan Naithani, Amit Kumar Tyagi
Blockchain has drawn attention as the next-generation financial technology due to its security that suits the informatization era. In particular, it provides security through the authentication of peers that share virtual cash, encryption, and the generation of hash value. According to the global financial industry, the market for security-based blockchain technology is expected to grow to about USD 20 billion by 2020. In addition, blockchain can be applied beyond the Internet of Things (IoT) environment; its applications are expected to expand. Cloud computing has been dramatically adopted in all IT environments for its efficiency and availability. In this paper, we discuss the concept of blockchain technology and its hot research trends. In addition, we will study how to adapt blockchain security to cloud computing and its secure solutions in detail.
Open access
2 source records
Blockchain Technology Applications and Security
IoT and Edge/Fog Computing
Advanced Steganography and Watermarking Techniques
Tien Tuan Anh Dinh, Rui Liu, Meihui Zhang, Gang Chen · 6 authors
Blockchain technologies are gaining massive momentum in the last few years. Blockchains are distributed ledgers that enable parties who do not fully trust each other to maintain a set of global states. The parties agree on the existence, values, and histories of the states. As the technology landscape is expanding rapidly, it is both important and challenging to have a firm grasp of what the core technologies have to offer, especially with respect to their data processing capabilities. In this paper, we first survey the state of the art, focusing on private blockchains (in which parties are authenticated). We analyze both in-production and research systems in four dimensions: distributed ledger, cryptography, consensus protocol, and smart contract. We then present BLOCKBENCH, a benchmarking framework for understanding performance of private blockchains against data processing workloads. We conduct a comprehensive evaluation of three major blockchain systems based on BLOCKBENCH, namely Ethereum, Parity, and Hyperledger Fabric. The results demonstrate several trade-offs in the design space, as well as big performance gaps between blockchain and database systems. Drawing from design principles of database systems, we discuss several research directions for bringing blockchain performance closer to the realm of databases.
Steven Goldfeder, Harry Kalodner, Dillon Reisman, Arvind Narayanan
Abstract We show how third-party web trackers can deanonymize users of cryptocurrencies. We present two distinct but complementary attacks. On most shopping websites, third party trackers receive information about user purchases for purposes of advertising and analytics. We show that, if the user pays using a cryptocurrency, trackers typically possess enough information about the purchase to uniquely identify the transaction on the blockchain, link it to the user’s cookie, and further to the user’s real identity. Our second attack shows that if the tracker is able to link two purchases of the same user to the blockchain in this manner, it can identify the user’s cluster of addresses and transactions on the blockchain, even if the user employs blockchain anonymity techniques such as CoinJoin. The attacks are passive and hence can be retroactively applied to past purchases. We discuss several mitigations, but none are perfect.
A decentralized online quantum cash system, called qBitcoin, is given. We design the system which has great benefits of quantization in the following sense. Firstly, quantum teleportation technology is used for coin transaction, which prevents from the owner of the coin keeping the original coin data even after sending the coin to another. This was a main problem in a classical circuit and a blockchain was introduced to solve this issue. In qBitcoin, the double-spending problem never happens and its security is guaranteed theoretically by virtue of quantum information theory. Making a block is time consuming and the system of qBitcoin is based on a quantum chain, instead of blocks. Therefore a payment can be completed much faster than Bitcoin. Moreover we employ quantum digital signature so that it naturally inherits properties of peer-to-peer (P2P) cash system as originally proposed in Bitcoin.