4차산업혁명 시대는 새로운 도전을 하게 만들었으며, 특히 블록체인 기술은 많은 혁신 기술의 발전을 견인하고, 이제는 블록체인 생태계를 구축하여 많은 사용 사례를 창출하고 일반화되어 가는 기술로 볼 수 있다. 이러한 블록체인 기술을 처리하기 위한 도커 컨테이너(Docker Container) 사용 확산 추세에 발맞추어, 본 연구에서는 도커 컨테이너에 기초한 오픈 소스 하이퍼레저 컴포즈(Hyperledger Composer) 비즈니스 네트워크 구현을 실행하였다. 도커 컨테이너의 환경설정, 커밋 그리고 웹 브라우저를 통한 블록체인 사용 절차를 살펴보고 실제적인 비즈니스 모델을 구현하였다. 본 연구는 도커 컨테이너의 이해, 블록체인 하이퍼레저 컴포저 참여자 및 거래 처리 방법을 구현하고, 실제로 비즈니스 네트워크 블록을 만들어 실행하였다. 이를 통하여 오픈 소스 하이퍼레저 컴포저 블록체인 기술의 근간을 이해하고, 하이퍼레저 컴포즈 블록체인 기술의 사용 확산과 여러 비즈니스 환경에서의 응용에 기여하고자 한다.The era of the fourth industrial revolution has created a new challenge. In particular, the block chain technology has led to the development of many innovative technologies, and now it can be seen as a technology that creates many use cases and becomes generalized by building a block chain ecosystem. In keep ing with the trend of using Docker Containers to handle these block chain technologies, we have implemented an open source Hyperledger Composer business network based on a Container of Docker. We set up an actual business model by examining the configuration of the container, the commit, and the block chain using the web browser. Based on the understanding of the Docker Container, this study materialized the block chain Hyperledger Composer participant and transaction processing method, and eventually created and executed the business network block. Through this, we will be able to understand the fundamentals of open source Hyperledger Composer block chain technology and will ultimately contribute to the spread of use of Hyperledger Composer block chain technology and its application in various business environments.
Blockchain is defined as a distributed ledger technology that can implement financial models. An improved blockchain provides a democratic virtual economic system (DVES) that can verify payments, reach consensus, and store encrypted data in virtual economic systems. In this paper, we review the latest progress and possibilities in improved blockchain with respect to openness, data security, and scalability. This paper outlines the challenges of value, existence, and status (VES) and the state-of-the-art solutions for improved blockchain. Then, this paper discusses the VES in terms of distributed energy, ownership certification, infrastructure, and other fields. More importantly, it analyzed the importance of scale out, which can be a key enabler to solve the main practical problems in constructing DVES.
In recent years, the rapid development of Cloud, Edge and Internet of Things (IoT) technologies has accelerated the advancement trends forcing applications and information systems (IS) to evolve. In this new ecosystem, ISs are federated and usually highly distributed becoming complex and very dynamic that have to extend not only through the Cloud/Edge and IoT layers but also the federated organizational boundaries. In this context, Osmotic Computing (OC) is a new paradigm driven by the significant increase in capacity/capability of resources in highly distributed and federated environments, that solves problems related to the deployment, networking and security of microservices called MicroElements (MEL) that are composed and interconnected over Cloud/Edge and IoT infrastructures with specified levels of QoS and security constraints. In this federated collaborative system, each organization needs to have proper administration and security policies to maintain data security while allowing selective sharing of resources. Classical models of access control are not effective in protecting resources while allowing users to access to the resources within their privileges. Blockchain is an underlying technology that could help organizations to improve access control systems through consensus mechanisms, and underlying features of immutability, transparency, auditability, and cryptography. In this work, we propose a MELs orchestration approach through a Software Defined Membrane (SDMem) that leverages Blockchain facilities obeying the osmosis principles.
This paper proposes and implements a method to verify the blockchain healthiness and to detect a malicious node using data collected from the IoT blockchain such as the transaction generation interval, the blockchains generation rate, and the statistics of IoT data stored in the blockchain. Furthermore, this paper proposes, designs, and implements a visualization tool to efficiently monitor the blockchain healthiness and IoT data in a consistent view via visualization of real-time blockchain update events, blockchain network statistics, and finally the IoT sensing data stored in blockchain as a transaction.
The logging system records the logs generated by the software so that the administrator can handle the problems that occur. However, the traditional log system is not secure enough and the stored logs are easily falsified. As a decentralized distributed storage technology, the blockchain can ensure that the blockchain network works normally in the presence of a few malicious nodes or failed nodes. So we use the blockchain to store the logs, which improves the security of the log system. In order to improve the performance of the blockchain, we use a voting-based consensus algorithm as a blockchain consistency protocol. This article introduces the architecture and implementation of the log system and verifies the feasibility of the system through experiments.
Daniela Mechkaroska, Aleksandra Popovska‐Mitrovikj, Vesna Dimitrova
BlockChain is a distributed database of records or public ledger of all time stamped transactions saved in all computers in one peer-to-peer network. It allows a secure and transparent transfer of digital goods including money and intellectual property. Bitcoin - a digital decentralized cryptocurrency, is the first application of BlockChain. The second application is an agreement called Smart contract that enables exchanging a value or assets between two owners based on a set of conditions included in the contract.
In this paper, we analyze the possibilities for application of BlockChain in Big Data and IoT. Implementation of BlockChain in Big Data confirms that data is accurate and secure and sharing of data will become more simple. In industries like financial services, government and healthcare there is a need to combine BlockChain and Big Data because these industries have repositories full of important data. They must store and share these large amounts of data. Implementation of BlockChain technology provides security of data and ensures its integrity when shared. BlockChain technology is also seen as a way to secure the Internet of Things (IoT). Application of BlockChain in IoT enables IoT devices to participate in BlockChain transactions and invents new styles of digital interactions. This technology will provide a simple infrastructure for devices to directly and securely transfer data or money using Smart contract.
In a research community, the provenance sharing of scientific workflows can enhance distributed research cooperation, experiment reproducibility verification and experiment repeatedly doing. Considering that scientists in such a community are often in a loose relation and distributed geographically, traditional centralized provenance sharing architectures have shown their disadvantages in poor trustworthiness, reliabilities and efficiency. Additionally, they are also difficult to protect the rights and interests of data providers. All these have been largely hindering the willings of distributed scientists to share their workflow provenance. Considering the big advantages of blockchain in decentralization, trustworthiness and high reliability, an approach to sharing scientific workflow provenance based on blockchain in a research community is proposed. To make the approach more practical, provenance is handled on-chain and original data is delivered off-chain. A kind of block structure to support efficient provenance storing and retrieving is designed, and an algorithm for scientists to search workflow segments from provenance as well as an algorithm for experiments backtracking are provided to enhance the experiment result sharing, save computing resource and time cost by avoiding repeated experiments as far as possible. Analyses show that the approach is efficient and effective.
Blockchain is one of the technology that has created a disruptive change in many industries. Currently, Blockchain is being used in several places and there are many more applications of Blockchain yet to be discovered and implemented. Blockchain is characterized by its decentralized nature, integrity of the data stored in the chain and its openness. Due to these characteristics, another place where Blockchain can be used is to release government funds for a project. Usually when a project is allocated funds, there is no knowledge as to how these funds are being used and a large part of it is never shown in records due to corruption. To solve this problem, a system has been proposed using Blockchain to provide the transparency. This paper also gives a description about a prototype which was developed using Hyperledger Composer. It then discusses the future development of this prototype and finally, concludes with the applicability of Blockchain.
Blockchain is an emerging decentralized infrastructure and distributed computing paradigm. Blockchain has been widely used in many industries including finance, energy, and cloud computing. Consortium blockchain is known as the permissioned blockchain, in which each user needs to be authorized. Distributed consensus is the core issue of consortium blockchain technology. In order to solve the disadvantages of using Proof of Work (POW) algorithm in consortium blockchain, such as computing resources waste, long block confirmation delay and low throughput, we designed and implemented a high performance blockchain consensus algorithm based on message passing technology called HPBC. HPBC algorithm can work well in asynchronous networks with Byzantine nodes. Results from theoretical analysis and performance evaluation show that HPBC algorithm provides safe and reliable distributed consensus services in consortium blockchain with low overhead. Finally, we summarized HPBC algorithm and briefly explore its further research directions.
Bitcoin-derived blockchain has shown promise as infrastructure for many decentralized models. However, problems are withholding the realization of the potentials. The booming increase of storage demand has hindered devices with storage shortage to use blockchain powered distributed applications. In this paper, we present section-blockchain, a new blockchain protocol, which is designed to solve the oversize storage problem without compromise the security of blockchain. There are no full nodes or lightweight nodes, all nodes are equal and contributing to the Section-Blockchain network. Experiments demonstrate that Section-Blockchain is efficient, remarkably reduced the storage, and withstand sudden nodes losing of massive scale. Section-blockchain also extended the capability of blockchain to the foundation of an autotrophic, tamper-resist decentralized storage system, in which, data can be equidistributional distributed worldwide automatically without any centralized dispatcher to assign storage; nodes are motivated to change their local storage to receive more remuneration. The global storage distribution is continuously optimizing and fit into any adding/losing nodes.
Eranga Bandara, Wee Keong Ng, Kasun De Zoysa, Owen Noel Newton Fernando · 7 authors
Blockchain is a peer-to-peer distributed storage that stores chronological series of transactions in a tamper-resistant manner. Blockchain became popular in various industries due to its decentralized trust ecosystem. When integrating blockchain with big data, one encounters many challenges. Current public blockchain does not support high transaction throughput; it does not scale in terms of big data storage and management; it does not provide keyword-based search and retrieval; and so on. As a result, it is hard to incorporate existing blockchain systems for big data applications. In this research, we propose a new blockchain storage "Mystiko" that is built over the Apache Cassandra distributed database to incorporate big data. Mystiko supports high transaction throughput, high scalability, high availability and full text search features. With Mystiko, we make big data more secure, structured and meaningful, and allows further data analytics on big data to be more easily performed.
Internet of Things (IoT) is the current technological breakthrough, enabling computing and sensing devices embedded in everyday processes to seamlessly exchange data, thus shaping the smart-everything concept. Alongside IoT, blockchain is transforming Internet by enabling Trustless, Distributed and Secure exchange of everything of value. In this paper, we propose a distributed sensor node system that utilizes IOTA protocol, a novel distributed ledger technology, to exchange data in an M2M fashion and establish a data monetization economy paradigm.
Lars Pilgaard Mikkelsen, Kasper Mortensen, Henrik Rasmussen, Hans-Peter Schwefel · 5 authors
Usage of IoT marketplaces as central components in distributed systems have become common, as they allow for easy exploitation of other services and data sources. When relying on a marketplace to be available in order for a system to be operational, it is critical that the marketplace operation is highly robust. Marketplaces are typically centralized components which means that single point of failure is a possible issue. Also users of the marketplace must trust the operator to be fair and follow a common set of rules. This work proposes to utilize blockchain technology to realize a distributed marketplace where both functionalities and storage are distributed and thereby increasing availability to users, while removing the need for a central operator. The blockchain also makes the operational rules transparent to the users of the marketplace. In this relation two core marketplace functionalities, offering creation and discovery, are realized using smart contracts on a private Ethereum blockchain and evaluated using an experimental testbed. The results demonstrate the feasibility of a blockchain based marketplace implementation.
This paper presents a stochastic model for block arrival times based on the difficulty retargeting rule used in Bitcoin, as well as other proof-of-work blockchains. Unlike some previous work, this paper explicitly models the difficulty target as a random variable which is a function of the previous block arrival times and affecting the block times in the next retargeting period. An explicit marginal distribution is derived for the time between successive blocks (the blocktime), while allowing for randomly changing difficulty. This paper also aims to serve as an introduction to Bitcoin and proof-of-work blockchains for the controls community, focusing on the difficulty retargeting procedure used in Bitcoin.
Rafael Brundo Uriarte, Rocco De Nicola, Kyriakos Kritikos
Cloud services operate in a highly dynamic environment. This means that they need to be assorted with dynamic SLAs which explicate how a rich set of QoS guarantees evolves over time. Only in this way, cloud users will trust and thus migrate their processes to the cloud. Research-wise, SLAs are assumed to include single states while they are managed mainly in a centralised manner. This paper proposes a framework to manage dynamic SLAs in a distributed manner by relying on a rich and dynamic SLA formalism which is transformed into a smart contract. This contract is then handled via the blockchain which exploits an oracle-based interface to retrieve the off-chain cloud service context sensed and enforce the right SLA management/modification functions. The proposed framework can change the current shape of the cloud market by catering for the notion of an open distributed cloud which offers manageable and dynamic services to cloud customers enabling them to reduce costs and increase the flexibility in resource management.
Today's commercial model for edge computing services consists in lightweight devices at the network edge connected through the Internet to remote cloud data centers. Microclouds are an alternative vision of edge computing, where the cloud infrastructure runs at the network edge leveraging decentralized resource contributions of a community. But current attempts to build such microclouds lack a collaborative governance system to operate successfully. In this paper we discuss the opportunity to implement with blockchain technologies key services to enable the decentralized collaborative governance of microclouds. A multiagent approach could further contribute to improve the efficiency in the decision making in the collaborative governance service.
Blockchain technology has received great attention in recent years. However, the data volume of blockchain grows continuously due to the features that cannot be deleted and can only be added. Currently, the total size of Bitcoin blockchain ledger has reached 200GB. Its high demand for storage space and bandwidth to synchronize data with the network prevents many nodes from joining the network.This is not only not conducive to the expansion of this decentralized network, but also becomes the bottleneck of the development of blockchain technology. This paper proposes an IPFS-based blockchain data storage model to solve this problem.In this paper, the miners deposit the transaction data into the IPFS network and pack the returned IPFS hash of transaction into the block. Utilizing the characteristics of the IPFS network and the features of the IPFS hash, the blockchain data is greatly reduced. The scheme is applied to the Bitcoin blockchain. According to the experimental results, the compression ratio can reach 0.0817. According to the analysis, it also has good performance in terms of security and synchronization speed of new node.
Blockchain technology has seen significant growth, hype, and potential new developments over the past few years. In this article additional insights into how blockchain can add value to a business process relationship is detailed. Specifically an engineering contract workflow use application pilot including various high level system architectural aspects are presented. This application shows the integration of blockchain technology with existing legacy systems. Some management and technology issues are also overviewed for the reader.
In this paper, we consider the problem of fair scheduling of transactions of multiple types that are submitted to a permissioned blockchain system. Permissioned blockchains are being increasingly used for enterprise applications and by design are heterogeneous in nature, with different peer organizations performing different business functions. Transactions execute different smart contract operations that may have widely varying business importance. In such a setting, we argue that the typically adopted First-In-First-Out ordering mechanism for transactions in a blockchain system, which is a performance-limited resource, is inefficient and unfair. We propose a weighted fair queueing strategy for ordering transactions that can support differentiated quality of service for submitted transactions on the blockchain. The main challenge we address in this paper is to support fair allocation and differentiation in a decentralized manner, as there is no single authority that can facilitate this as in traditional systems. We demonstrate such a fair scheduling strategy and support multiple transaction types with different priorities on Hyperledger Fabric.
Muhammad Ahmad Zafar, Falak Sher, Muhammad Umar Janjua, Salman Baset
Could smart contracts written in Solidity, a popular language among blockchain developers for Ethereum, be run on other blockchain platforms such as Hyperleger Fabric. To run Solidity smart contracts on another blockchain platform, one can either incorporate the Ethereum Virtual Machine (EVM) in the target blockchain, or perform a source-to-source translation of the Solidity contracts to a smart contract language for the target platform. This paper presents Sol2js, an open source source-to-source translation tool that generates Javascript smart contracts for Hyperledger Fabric from Solidity contracts, and provides a conceptual mapping of Ethereum constructs to that of Hyperleger Fabric, where possible. Presently, the tool is able to successfully translate 65-70% of Solidity constructs including major types, functions, inheritance, and events. The preliminary results show that the average of the lines of code (loc) across translated contracts is 7.5x more than the average of Solidity contracts loc while preserving contract semantics.