Abstract: Blockchain is a decentralized transaction and data management technology developed first for Bitcoin cryptocurrency. The interest in Blockchain technology has been increasing since the idea was coined in 2008. The reason for the interest in Blockchain is its central attributes that provide security, anonymity and data integrity without any third party organization in control of the transactions, and therefore it creates interesting research areas, especially from the perspective of technical challenges and limitations. In this research, we have conducted a systematic mapping study with the goal of collecting all relevant research on Blockchain technology. Our objective is to understand the current research topics, challenges and future directions regarding Blockchain technology from the technical perspective. We have extracted 41 primary papers from scientific databases. The results show that focus in over 80% of the papers is on Bitcoin system and less than 20% deals with other Blockchain applications including e.g. smart contracts and licensing. The majority of research is focusing on revealing and improving limitations of Blockchain from privacy and security perspectives, but many of the proposed solutions lack concrete evaluation on their effectiveness. Many other Blockchain scalability related challenges including throughput and latency have been left unstudied. On the basis of this study, recommendations on future research directions are provided for researchers.

Abstract: This paper expounds the main principles behind blockchain technology and some of its cutting-edge applications. Firstly, we present the core concepts at the heart of the blockchain, and we discuss the potential risks and drawbacks of public distributed ledgers, and the shift toward hybrid solutions. Secondly, we expose the main features of decentralized public ledger platforms. Thirdly, we show why the blockchain is a disruptive and foundational technology, and fourthly, we sketch out a list of important applications, bearing in mind the most recent evolutions.

Abstract: The technology likely to have the greatest impact on the future of the world economy has arrived, and its not self-driving cars, solar energy, or artificial intelligence. Its called the blockchain. The first generation of the digital revolution brought us the Internet of information. The second generationpowered by blockchain technologyis bringing us the Internet of value: a new, distributed platform that can help us reshape the world of business and transform the old order of human affairs for the better. Blockchain is the ingeniously simple, revolutionary protocol that allows transactions to be simultaneously anonymous and secure by maintaining a tamperproof public ledger of value. Though its the technology that drives bitcoin and other digital currencies, the underlying framework has the potential to go far beyond these and record virtually everything of value to humankind, from birth and death certificates to insurance claims and even votes. Why should you care? Maybe youre a music lover who wants artists to make a living off their art. Or a consumer who wants to know where that hamburger meat really came from. Perhaps youre an immigrant whos sick of paying big fees to send money home to loved ones. Or an entrepreneur looking for a new platform to build a business. And those examples are barely the tip of the iceberg. This technology is public, encrypted, and readily available for anyone to use. Its already seeing widespread adoption in a number of areas. For example, forty-two (and counting) of the worlds biggest financial institutions, including Goldman Sachs, JPMorgan Chase, and Credit Suisse, have formed a consortium to investigate the blockchain for speedier and more secure transactions. As with major paradigm shifts that preceded it, the blockchain will create winners and losers. And while opportunities abound, the risks of disruption and dislocation must not be ignored. Don Tapscott, the bestselling author of Wikinomics, and his son, blockchain expert Alex Tapscott, bring us a brilliantly researched, highly readable, and utterly foundational book about the future of the modern economy. Blockchain Revolution is the business leaders playbook for the next decade and beyond.

Abstract: Cryptocurrencies, based on and led by Bitcoin, have shown promise as infrastructure for pseudonymous online payments, cheap remittance, trustless digital asset exchange, and smart contracts. However, Bitcoinderived blockchain protocols have inherent scalability limits that trade off between throughput and latency, which withhold the realization of this potential. This paper presents Bitcoin-NG (Next Generation), a new blockchain protocol designed to scale. Bitcoin-NG is a Byzantine fault tolerant blockchain protocol that is robust to extreme churn and shares the same trust model as Bitcoin. In addition to Bitcoin-NG, we introduce several novel metrics of interest in quantifying the security and efficiency of Bitcoin-like blockchain protocols. We implement Bitcoin-NG and perform large-scale experiments at 15% the size of the operational Bitcoin system, using unchanged clients of both protocols. These experiments demonstrate that Bitcoin-NG scales optimally, with bandwidth limited only by the capacity of the individual nodes and latency limited only by the propagation time of the network.

Abstract: Blockchain technology has the potential to revolutionize applications and redefine the digital economy

Abstract: In the Internet of Things (IoT) scenario, the block-chain and, in general, Peer-to-Peer approaches could play an important role in the development of decentralized and dataintensive applications running on billion of devices, preserving the privacy of the users. Our research goal is to understand whether the blockchain and Peer-to-Peer approaches can be employed to foster a decentralized and private-by-design IoT. As a first step in our research process, we conducted a Systematic Literature Review on the blockchain to gather knowledge on the current uses of this technology and to document its current degree of integrity, anonymity and adaptability. We found 18 use cases of blockchain in the literature. Four of these use cases are explicitly designed for IoT. We also found some use cases that are designed for a private-by-design data management. We also found several issues in the integrity, anonymity and adaptability. Regarding anonymity, we found that in the blockchain only pseudonymity is guaranteed. Regarding adaptability and integrity, we discovered that the integrity of the blockchain largely depends on the high difficulty of the Proof-of-Work and on the large number of honest miners, but at the same time a difficult Proof-of-Work limits the adaptability. We documented and categorized the current uses of the blockchain, and provided a few recommendations for future work to address the above-mentioned issues.

Abstract: Internet of Things (IoT) are being adopted for industrial and manufacturing applications such as manufacturing automation, remote machine diagnostics, prognostic health management of industrial machines and supply chain management Cloud-Based Manufacturing is a recent on-demand model of manufacturing that is leveraging IoT technologies While Cloud-Based Manufacturing enables on-demand access to manufacturing resources, a trusted intermediary is required for transactions between the users who wish to avail manufacturing services We present a decentralized, peer-to-peer platform called BPIIoT for Industrial Internet of Things based on the Block chain technology With the use of Blockchain technology, the BPIIoT platform enables peers in a decentralized, trustless, peer-to-peer network to interact with each other without the need for a trusted intermediary

Abstract: Blockchain, widely known as one of the disruptive technologies emerged in recent years, is experiencing rapid development and has the full potential of revolutionizing the increasingly centralized intelligent transportation systems (ITS) in applications. Blockchain can be utilized to establish a secured, trusted and decentralized autonomous ITS ecosystem, creating better usage of the legacy ITS infrastructure and resources, especially effective for crowdsourcing technology. This paper conducts a preliminary study of Blockchain-based ITS (B2ITS). We outline an ITS-oriented, seven-layer conceptual model for blockchain, and on this basis address the key research issues in B2ITS. We consider that blockchain is one of the secured and trusted architectures for building the newly developed parallel transportation management systems (PtMS) , and thereby discuss the relationship between B2ITS and PtMS. Finally, we present a case study for blockchain-based realtime ride-sharing services. In our viewpoint, B2ITS represents the future trend of ITS research and practice, and this paper is aimed at stimulating further effort and providing helpful guidance and reference for future research works.

Abstract: The integration of business processes across organizations is typically beneficial for all involved parties. However, the lack of trust is often a roadblock. Blockchain is an emerging technology for decentralized and transactional data sharing across a network of untrusted participants. It can be used to find agreement about the shared state of collaborating parties without trusting a central authority or any particular participant. Some blockchain networks also provide a computational infrastructure to run autonomous programs called smart contracts. In this paper, we address the fundamental problem of trust in collaborative process execution using blockchain. We develop a technique to integrate blockchain into the choreography of processes in such a way that no central authority is needed, but trust maintained. Our solution comprises the combination of an intricate set of components, which allow monitoring or coordination of business processes. We implemented our solution and demonstrate its feasibility by applying it to three use case processes. Our evaluation includes the creation of more than 500 smart contracts and the execution over 8,000 blockchain transactions.

Abstract: The ‘blockchain’ is the core mechanism for the Bitcoin digital payment system. It embraces a set of inter-related technologies: the blockchain itself as a distributed record of digital events, the distributed consensus method to agree whether a new block is legitimate, automated smart contracts, and the data structure associated with each block. We propose a permanent distributed record of intellectual effort and associated reputational reward, based on the blockchain that instantiates and democratises educational reputation beyond the academic community. We are undertaking initial trials of a private blockchain or storing educational records, drawing also on our previous research into reputation management for educational systems.

Abstract: Blockchain is an emerging technology for decentralized and transactional data sharing across a large network of untrusted participants. It enables new forms of distributed software architectures, where components can find agreements on their shared states without trusting a central integration point or any particular participating components. Considering the blockchain as a software connector helps make explicitly important architectural considerations on the resulting performance and quality attributes (for example, security, privacy, scalability and sustainability) of the system. Based on our experience in several projects using blockchain, in this paper we provide rationales to support the architectural decision on whether to employ a decentralized blockchain as opposed to other software solutions, like traditional shared data storage. Additionally, we explore specific implications of using the blockchain as a software connector including design trade-offs regarding quality attributes.

Abstract: Blockchain has become a new frontier of venture capitals that has attracted the attention of banks, governments, and other business corporations. The recent blockchain related attempts included legal blockchains by Fadada.com and Microsoft and pork tracking blockchains by Walmart and IBM. Blockchain is poised to become the most exciting invention after the Internet; while the latter connects the world to enable new business models based on online business processes, the former will help resolve the trust issue more efficiently via network computing. In this paper, we give an overview on blockchain research and development as well as introduce the papers in this special issue. We show that while blockchain has enabled Bitcoin, the most successful digital currency, its widespread adoption in finance and other business sectors will lead to many business innovations as well as many research opportunities.

Abstract: This article provides insight into how “Blockchains” work. A block chain or Blockchain is a distributed database that maintains a continuously growing list of data records that are hardened against tampering and revision, even by operators of the data store's nodes. One can view a Blockchain as a public ledger of all transactions that have ever been executed. It is constantly growing as completed blocks are added to previous blocks forming a chain. Importantly, blocks are added to the Blockchain in a linear, chronological order. Each miner gets a copy of the Blockchain when joining the Bitcoin network. The Blockchain they receive has complete and accurate information about the addresses and their balances right from the genesis block to the most recently completed block. © 2016 Wiley Periodicals, Inc.

Abstract: Purpose The purpose of this paper is to explore the value of Blockchain technology as a solution to creating and preserving trustworthy digital records, presenting some of the limitations, risks and opportunities of the approach. Design/methodology/approach The methodological approach involves using the requirements embedded in records management and digital preservation standards, specifically ISO 15,489, ARMA’s Generally Accepted Recordkeeping Principles, ISO 14,721 and ISO 16,363, as a general evaluative framework for a risk-based assessment of a specific proposed implementation of Blockchain technology for a land registry system in a developing country. Findings The results of the analysis suggest that Blockchain technology can be used to address issues associated with information integrity in the present and near term, assuming proper security architecture and infrastructure management controls. It does not, however, guarantee reliability of information in the first place, and would have several limitations as a long-term solution for maintaining trustworthy digital records. Originality/value This paper contributes an original analysis of the application of Blockchain technology for recordkeeping.

Abstract: An interesting research problem in our age of Big Data is that of determining provenance. Granular evaluation of provenance of physical goods -- e.g. tracking ingredients of a pharmaceutical or demonstrating authenticity of luxury goods -- has often not been possible with today's items that are produced and transported in complex, inter-organizational, often internationally-spanning supply chains. Recent adoption of Internet of Things and Blockchain technologies give promise at better supply chain provenance. We are particularly interested in the blockchain as many favoured use cases of blockchain are for provenance tracking. We are also interested in applying ontologies as there has been some work done on knowledge provenance, traceability, and food provenance using ontologies. In this paper, we make a case for why ontologies can contribute to blockchain design. To support this case, we analyze a traceability ontology and translate some of its representations to smart contracts that execute a provenance trace and enforce traceability constraints on the Ethereum blockchain platform.

Abstract: A blockchain is a distributed and decentralized ledger that contains connected blocks of transactions. Unlike other ledger approaches, blockchain guarantees tamper proof storage of approved transactions. Due to its distributed and decentralized organization, blockchain is beeing used within IoT e.g. to manage device configuration, store sensor data and enable micro-payments. This paper presents the idea of using blockchain as a service for IoT and evaluates the performance of a cloud and edge hosted blockchain implementation.

Abstract: Claims blockchain is more than just ICT innovation, but facilitates new types of economic organization and governance. Suggests two approaches to economics of blockchain: innovation-centred and governance-centred. Argues that the governance approach — based in new institutional economics and public choice economics — is most promising, because it models blockchain as a new technology for creating spontaneous organizations, i.e. new types of economies. Illustrates this with a case study of the Ethereum-based infrastructure protocol and platform Backfeed.

Abstract: A new mechanism is proposed for securing a blockchain applied to contracts management such as digital rights management. This mechanism includes a new consensus method using a credibility score and creates a hybrid blockchain by alternately using this new method and proof-of-stake. This makes it possible to prevent an attacker from monopolizing resources and to keep securing blockchains.

Abstract: A computer system is provided that communicates with a distributed blockchain computing system that includes multiple computing nodes. The exchange stores an order book and a plurality of digital wallets associated with different clients. The computer system receives new data transaction requests that are added to the order book. A match is identified between data transaction requests and hashes associated with the digital wallets associated with the respective data transaction requests are generated. The counterparties receive the hashes of the other party along with information on the match and each party causes blockchain transactions to be added to the blockchain of the blockchain computing system. The computing system then monitors the blockchain to determine if both sides of the match has been added to the blockchain.

Abstract: We build on economic theory to discuss how blockchain technology can shape innovation and competition in digital platforms.We identify two key costs affected by the technology: the cost of verification and the cost of networking.The cost of verification relates to the ability to cheaply verify state, including information about past transactions and their attributes, and current ownership in a native digital asset.The cost of networking, instead, relates to the ability to bootstrap and operate a marketplace without assigning control to a centralized intermediary.This is achieved by combining the ability to cheaply verify state with economic incentives targeted at rewarding state transitions that are particularly valuable from a network perspective, such as the contribution of the resources needed to operate, scale, and secure a decentralized network.The resulting digital marketplaces allow participants to make joint investments in shared infrastructure and digital public utilities without assigning market power to a platform operator, and are characterized by increased competition, lower barriers to entry, and a lower privacy risk.Because of their decentralized nature, they also introduce new types of inefficiencies and governance challenges.

Abstract: An interesting research problem in our age of Big Data is that of determining provenance. Granular evaluation of provenance of physical goods--e.g. tracking ingredients of a pharmaceutical or demonstrating authenticity of luxury goods--has often not been possible with today's items that are produced and transported in complex, inter-organizational, often internationally-spanning supply chains. Recent adoption of Internet of Things and Blockchain technologies give promise at better supply chain provenance. We are particularly interested in the blockchain as many favoured use cases of blockchain are for provenance tracking. We are also interested in applying ontologies as there has been some work done on knowledge provenance, traceability, and food provenance using ontologies. In this paper, we make a case for why ontologies can contribute to blockchain design. To support this case, we analyze a traceability ontology and translate some of its representations to smart contracts that execute a provenance trace and enforce traceability constraints on the Ethereum blockchain platform.

Abstract: An electronic resource tracking and storage computer system is provided that communicates with a distributed blockchain computing system that includes multiple computing nodes. The system includes a storage system, a transceiver, and a processing system. The storage system includes an resource repository and transaction repository that stores submitted blockchain transactions. A new resource issuance request is received, and a new resource is added to the resource repository in response. A new blockchain transaction is generated and published to the blockchain. In correspondence with publishing to the blockchain, the transaction storage is updated with information that makes up the blockchain transaction and some information that was not included as part of the blockchain transaction. The transaction storage is updated when the blockchain is determined to have validated the previously submitted blockchain transaction.

Abstract: A method for authenticating a chain of custody utilizing blockchain technology, whereby digital evidence or other digital content is acquired and then hashed to produce a hash fingerprint/signature and then immediately or instantly submitting said hash fingerprint/signature to the blockchain using the blockchain network protocol, forming an immediate verifiable chain of custody without human interaction or requiring a trusted third party

Abstract: Equity crowdfunding via the Internet is a new channel of raising money for startups. It features low barriers to entry, low cost, and high speed, and thus encourages innovation. In recent years, equity crowdfunding in China has experienced some developments. However, some problems remain unsolved in practice. Blockchain is a decentralized and distributed ledger technology to ensure data security, transparency, and integrity. Because it cannot be tampered with or forged, the technology is deemed to have great potential in the finance industry. This study examines current problems in the practice of equity crowdfunding in China. Based on the analysis of the characteristics of blockchain technology, this study further explores its practical applications in equity crowdfunding. 1) Blockchain technology may be a secure, efficient, low-cost solution for the registration of stocks and shares of a firm financed by crowdfunding; 2) Blockchain technology simplifies the transaction and transfer of crowdfunding equities, and thus facilitates their circulation; 3) Blockchain technology enables peer to peer transactions between investors and entrepreneurs, and solves the problems of regulatory compliance and security of fund management; Blockchain technology can be used to develop a voting system for crowdfunders, which enables them to be involved in corporate governance. This helps protect the rights and interests of small investors; 5) Blockchain technology helps regulators know about market conditions, and supports regulatory activities such as managing investors and fighting money laundering.

Abstract: The first, foundational book on blockchain technology, from the bestselling author of Wikinomics Don Tapscott and blockchain expert Alex Tapscott, now in paperback with a new preface and chapter explaining recent developments in the world of blockchain, including cryptoassets, ICOs, smart contracts, and more. This book has had an enormous impact on the evolution of blockchain in the world. Satya Nadella, CEO, Microsoft Corporation In this revelatory book, Don and Alex Tapscott bring us a brilliantly researched, highly readable, and essential book about the technology driving the future of the economy. Blockchain is the ingeniously simple, revolutionary protocol that allows transactions to be simultaneously anonymous and secure by maintaining a tamperproof public ledger of value. Though its best known as the technology that drives bitcoin and other digital currencies, it also has the potential to go far beyond currency, to record virtually everything of value to humankind, from birth and death certificates to insurance claims, land titles, and even votes. As with major paradigm shifts that preceded it, blockchain technology will create winners and losers. This book shines a light on where it can lead us in the next decade and beyond.

Abstract: In recent years, blockchain technology has attracted considerable attention. It records cryptographic transactions in a public ledger that is difficult to alter and compromise because of the distributed consensus. As a result, blockchain is believed to resist fraud and hacking. This work explores the types of fraud and malicious activities that can be prevented by blockchain technology and identifies attacks to which blockchain remains vulnerable. This study recommends appropriate defensive measures and calls for further research into the techniques for fighting malicious activities related to blockchains.

Abstract: We put forward a new framework that makes it possible to re-write or compress the content of any number of blocks in decentralized services exploiting the blockchain technology. As we argue, there are several reasons to prefer an editable blockchain, spanning from the necessity to remove inappropriate content and the possibility to support applications requiring re-writable storage, to "the right to be forgotten." Our approach generically leverages so-called chameleon hash functions (Krawczyk and Rabin, NDSS '00), which allow determining hash collisions efficiently, given a secret trapdoor information. We detail how to integrate a chameleon hash function in virtually any blockchain-based technology, for both cases where the power of redacting the blockchain content is in the hands of a single trusted entity and where such a capability is distributed among several distrustful parties (as is the case with Bitcoin). We also report on a proof-of-concept implementation of a redactable blockchain, building on top of Nakamoto's Bitcoin core. The prototype only requires minimal changes to the way current client software interprets the information stored in the blockchain and to the current blockchain, block, or transaction structures. Moreover, our experiments show that the overhead imposed by a redactable blockchain is small compared to the case of an immutable one.

Abstract: The present invention relates to a securities trading system that utilizes a distributed blockchain ledger to conduct security transactions. Users are provided with cryptographic wallets that enable the users to access a peer-to-peer network of computing nodes on which the distributed blockchain ledger is managed. The securities made available through the network may be stored directly on the blockchain ledger itself. Smart contracts may be utilized to transfer the securities among the users and to verify that all transactions are in compliance with applicable regulatory rules and other restrictions.