BACKGROUND: A blockchain-based Electronic Health Record(EHR) data-sharing scheme was proposed to solve the problems of data sharing difficulties and privacy disclosure. METHODS: This paper designs a blockchain-based electronic health record model based on the characteristics of blockchain antitampering, decentralization, and distributed storage. Utilize blockchain network and distributed database to store encryption-related access control policies to prevent EHR data from being tampered with and leaked. Data security sharing protocol combines Distributed Key Generation (DKG) and reencryption. RESULTS: The protocol used the Delegated Proof of Stake(DPOS) algorithm to select the proxy node, which reencrypted the EHR to share data between a pair of users. Simulation experiments and comparative analysis showed that DPOS efficiency was higher than Proof of Work (POW) and slightly lower than the Practical Byzantine Fault Tolerance(PBFT). CONCLUSIONS: The scheme proposed in this paper is more decentralized and less computationally intensive.
Marco Radovancovici, Darius Galiş, Ciprian Pungilă
In this paper we perform a practical analysis of techniques for minting genetic information, in particular genomic data, as non-fungible tokens (NFTs) in supporting blockchains, and perform a wide-range analysis of the best and most efficient tools to ensure such data’s privacy, non-repudiation and storage efficiency. We analyze the demands of the NFT-driven blockchain ecosystem today, and discuss how we can apply common approaches in storing and accessing genomic data, such as compression methods and encryption techniques for it, to the NFT world. We perform a practical experiment of our assessment, and compare the publicly available tools and libraries for achieving the aforementioned goal, in order to determine which one provides the best results in terms of speed and storage efficiency, and draw relevant conclusions as to which approach is more beneficial to NFT-driven ecosystems where genomic data could be safely preserved and actively traded.
A tecnologia blockchain é uma espécie de banco de dados ou um livro razão, no qual é possível inserir e transmitir informações de uma forma totalmente segura, rápida e transparente, não centralizando a informação em apenas um ponto. Também conhecida como “<strong>protocolo de confiança</strong>“, essa tecnologia foi criada em 2008 por Satoshi Nakamoto<sup>1</sup>, sendo, na época, a principal inovação no mundo tecnológico do bitcoin, mas não se confunde com a criptomoeda, pois essa tecnologia também pode ser utilizada nos mais diversos segmentos, como na educação, alimentos, automobilístico, marketing, saúde, e também no direito. Essa nova tecnologia propõe imutabilidade, transparência e descentralização como principal medida de segurança, funcionando como se fosse um livro razão, público, sem intervenção de terceiros. É uma base de dados distribuída que guarda um registro de transações definitivas e a prova de violação, não permitindo alterações, pois armazena informações em blocos que dependem de outros blocos seguintes e posteriores, formando uma cadeia de blocos. Ademais, essas informações não ficam em um computador centralizado, como habitualmente ocorre nos armazenamento de dados padrões pelo mundo, mas sim em milhares de computadores, cada um com seu próprio backup. Dessa forma não permitindo falhas que comumente poderiam ocorrem em uma centralização dos dados, pois se um nó (computador) deixar a rede, os demais conectados já teriam parte daquele bloco para compor a ausência deste. Isso faz com que todas as informações estejam sempre disponíveis de forma segura, pois um atacante (hacker) não conseguiria modificar as informações de toda uma cadeia de blockchain.
In industrial and academic working environments, illegitimate academic certificates have been prepared by individuals who aim to be employed without completing regulated training and education programs. This violation has made an unjust confusion between genuine and fake certificates. Within the hiring process, employers thus need a reliable mechanism for verifying academic certificates that ensures the integrity of data. In accordance with this aim, blockchain technology has been introduced and deployed at some universities supporting fraud prevention or secure access to certificates. However, the method of handling knowledge in these educational systems was not investigated devotedly. This paper introduces an authentication framework of educational certificates that employed blockchain and ontology technologies, named BOCA. The learning ontology (LeOn), which was used to represent the central knowledge model of the system, was assigned to semantically manage the domain knowledge and link the educational data to the blockchain network. The system features, including the working process, the LeON ontological development, and the rule base construction, are described in detail. The system deployment on Hyperledger Fabric yielded promising experimental results. Ongoing work focuses on improving system performance and allowing semantic search on data blocks.
With the emergence of concepts such as Metaverse and Web 3.0, digital identity plays a very important role as one of its infrastructures. The traditional digital identity model is no longer suitable for the requirements of the digital economy to some extent at this stage. The traditional centralized identity management system has many drawbacks. For example, the owner of the digital identity does not actually control his own identity, and there is a risk of easy disclosure and theft of identity information. Blockchain technology has the characteristics of decentralization, tamper-proof, traceability, etc., which can effectively solve the problems of centralized digital identity. After analyzing and summarizing the evolution trend of digital identity from centralization to decentralization, this paper focuses on the Self-Sovereign Identity (SSI) based on blockchain. Based on the analysis and comparison of various SSI implementation schemes, the development difficulties of blockchain digital identity are summarized and the future development direction is pointed out.
Marc Pilkington, Erdita Kumaraku, Kejsi Bushi, Katia Haveri
Albania is a small country of the West Balkans situated in Southeast Europe still in the early stages of distributed ledger technology (DLT) adoption. In this research note, we begin to investigate the cryptocurrency regulatory framework and propose a national blockchain roadmap for the country. Albania was one of the first European nations to elaborate a cryptocurrency regulatory framework aimed at safeguarding users from the dangers of fraud and imposing sanctions in situations of misuse. Our proposed national blockchain roadmap includes emerging priorities such as licensed entities, digital divide reduction, remittances digitisation, Ethereum 2.0, blockchain FDI, e-voting, and the quadruple helix system.
During the COVID-19 pandemic, the uncertainty in the markets was also reflected in the demand for cryptocurrencies. This study aims to visually present the bibliometric analyzes of empirical studies on cryptocurrencies during the COVID-19 pandemic period (between 2020-2022). For this purpose, VOSviewer software was used to perform a bibliometric analysis of 30 selected studies. According to the results obtained, it is seen that the selected studies are mostly scanned in the SCOPUS and SSCI indexes of the journals published. Most studies were conducted in Malaysia, followed by Pakistan and Spain. 7 studies were conducted in Malaysia and 3 studies each in Pakistan and Spain. In the studies, it was seen that the technology acceptance model, planned behavior theory, and unified theory of acceptance and use of technology were used the most, respectively. Structural equation modeling was used in 23 studies. When the variables used were examined, it was understood that the most used variables were the intention, risk, trust, and attitude. Considering the uncertainties in the pandemic period and the characteristics of cryptocurrencies, it is thought that the variables used to make significant contributions to the literature and relevant persons.
Plateforme fiable utilisant la technologie DLT pour un environnement industriel basé sur l'IoT Les modèles économiques collaboratifs subissent une évolution innovante basée sur les technologies modernes telles que l'Internet des objets (IoT), l'intelligence artificielle (IA), le Cloud, etc. Dans ce contexte, un exemple type est celui des systèmes des chaines d'approvisionnement (supply chain). Néanmoins, les systèmes actuels opérant en mode centralisé sont incapables de gérer/analyser les quantités massives de données collectées. De plus, la prolifération des appareils IoT augmente le besoin de plateformes qui prennent en charge la transparence des données pour assurer une confiance totale dans le partage d'informations et pour permettre la collaboration fiable entre les différents partenaires. La Blockchain comme « Distributed Ledger Technology (DLT) » est une solution prometteuse pour les nouveaux défis technologiques des entreprises dans un environnent collaboratif. Elle est basée sur une plateforme cryptographiquement décentralisée, ce qui assure l'amélioration de la productivité des applications et la suppression de nombreuses limitations telles que le manque de confiance et la transparence des données. Cependant, avec la croissance des données IoT, la Blockchain fait face à de nombreux défis majeurs qui l'empêchent de s'intégrer dans les systèmes « supply chain ».Alors que de nombreuses améliorations pour la Blockchain sont en cours de développement, de test ou de création, Il convient de citer d'autres plateformes décentralisées qui pourraient répondre au contexte des « supply chains ». La nouvelle technologie DLT basée sur « Directed Acyclic Graph » (DAG), en tant qu'alternative à Blockchain, peut résoudre les inconvénients de la Blockchain pour répondre à toutes les exigences de « supply chains » y compris le passage à l'échelle avec un grand nombre de participants et appareils IoT dans son réseau. De plus, DAG réduit la taille du ‘Ledger' à l'aide de la technique « snapshot », et réduit les frais de transaction à une valeur négligeable. Aussi elle introduit la possibilité de travailler ‘offline'. Néanmoins, DAG présente des contraintes supplémentaires telles que les limitations résultantes des « smart contract » et l'absence d'un mécanisme de distribution des tâches. Pour cela, l'objectif de cette thèse est de définir une nouvelle plateforme de « supply chain » permettant l'intégration des différentes technologies DLT et qui prend en considération la prolifération de l'IoT et les besoins de nouveaux modèles de collaboration.Dans cette thèse, nous proposons de combiner les deux technologies Blockchain et DAG en une seule plateforme pour satisfaire les nouvelles exigences du marché tout en résolvant les limitations causées par les inconvénients de ces DLTs. De plus, nous proposons un algorithme distribué qui s'exécute du côté DAG pour distribuer les nombreuses tâches entre les différents appareils IoT, résultant en un système performant avec équilibre de charge. Par la suite, nous considérerons les aspects de confidentialité des données et nous étudions les impacts de la transparence des DLTs en mettant en lumière les projets de chaîne d'approvisionnement existants. L'étude propose plusieurs mécanismes qui pourraient être utilisés pour satisfaire les exigences des « supply chain ». Enfin, nous concluons que notre plateforme proposée dispose de l'infrastructure appropriée, y compris « smart contract » et « DAG » pour les améliorations requises.
Digital identity management system is the securi-ty infrastructure of computer and internet applications. However, currently, most of the digital identity management systems are faced with problems such as the difficulty of cross-domain authentication and interoperation, the lack of credibility of identity authentication, the weakness of the security of identity data. Although the advantages of block-chain technology have attached the attentions of experts and scholars in the field of digital identity management and many digital identity management systems based on block-chain have been built, the systems still can't completely solve the problems mentioned above. Therefore, in this pa-per, an effective digital identity management system model is proposed which combines technologies of self-sovereign identity and oracle with blockchain so as to pave a way in solving the problems mentioned above and constructing a secure and reliable digital identity management system.
Blockchain and cloud-edge computing techniques are promising technologies for next-generation, secure, and privacy-preserving data-sharing systems. By integrating these technologies, the data demands of many data users, such as research institutes, hospitals, manufacturers, etc., can be met. Despite this promising integration, it is yet to be understood how the vulnerability and uncertainties of wireless communication links between the data producers, blockchain systems, cloud-edge computing-based platforms, and data users, as well as unstable validation parameters can affect the overall performance of such blockchain-enabled data-sharing systems. In this article, we considered a collaborative data-sharing scheme, where multiple data providers and data users collaborate to accomplish data-sharing tasks through the proposed blockchain and cloud-edge computing schemes. We considered the spatial distribution of data providers and data users to follow the independent homogeneous Poisson point process, while the transactions generation rate at each node was also modeled using an independent Bernoulli process. We then obtained analyses for some selected performance metrics of interest and evaluate the performance of the system. The obtained results showed that the proposed analyses can be useful in investigating the performance of any blockchain-enabled data-sharing system. This will aid successful deployments of effective data-sharing systems.
Jun 1, 2022·2022 IEEE 9th International Conference on Cyber Security and Cloud Computing (CSCloud)/2022 IEEE 8th International Conference on Edge Computing and Scalable Cloud (EdgeCom)
Blockchain technology has developed rapidly in recent years. Especially, in China, it is included in country’s new information infrastructure. As one of the important digital technologies for China’s digital economy, blockchain has many applications in the financial industry, and the development of financial blockchain standards has also been widely carried out. The four major international standardization organizations and China’s financial blockchain standardization have achieved preliminary results, but there are still some problems in the financial blockchain at present. The next step can be carried out from four aspects: building a standard system, strengthening the supervision of financial blockchain, participating in international standardization affairs and training of standardized talents.
Jun 1, 2022·2022 IEEE 9th International Conference on Cyber Security and Cloud Computing (CSCloud)/2022 IEEE 8th International Conference on Edge Computing and Scalable Cloud (EdgeCom)
Standards are an important key to the success of developing technologies, and formulating the right standards at the right time for technology development helps ensure the ease of use and interoperability of the technology, and blockchain technology is no exception. As blockchain technology has been officially incorporated into China’s new information infrastructure category, the application field of blockchain has expanded rapidly, gradually extending from the financial field and government affairs to other fields in the real economy. The real implementation of blockchain is inseparable from the open a complete standard system. The development of international standards aims to standardize the applications of blockchain, which can effectively break through the cognitive and technical barriers between different countries, industries and systems on a global scale, prevent application risks, and provide a standard basis for the development of the global blockchain industry. From the perspective of international standardization, this paper summarizes the current status of IEEE standards in the field of blockchain, comparatively analyzes the current status of major international standards organizations ISO, ITU-T and IEEE in the field of blockchain standards, focusing on the current status of IEEE blockchain standards analyzed, analyzed the characteristics of IEEE in blockchain technology standards and application standards. Through data analysis, carry out the planning and layout of future standards, assist the development of international standardization, promote the application and implementation of blockchain technology, and promote the joint application and development of blockchain technology in various industries.
Big Data and Digital Economy
Physical Unclonable Functions (PUFs) and Hardware Security
Jun 1, 2022·2022 IEEE 9th International Conference on Cyber Security and Cloud Computing (CSCloud)/2022 IEEE 8th International Conference on Edge Computing and Scalable Cloud (EdgeCom)
In recent years, blockchain technology has become one of the key technical innovation fields in the world. From the simple Bitcoin that can only be transferred at first to the blockchain application ecology that is now blooming, blockchain is gradually building a credible internet of value. However, with the continuous development and application of blockchain, even the blockchain based on cryptography is facing a series of network security problems and has caused great property losses to participants. Therefore, studying blockchain security and accelerating standardization of blockchain security have become the top priority to ensure the orderly and healthy development of blockchain technology. This paper briefly introduces the scope of blockchain security from the perspective of network security, sorts out some existing standards related to blockchain security, and gives some suggestions to promote the development and application of blockchain security standardization.
Jun 1, 2022·2022 IEEE 9th International Conference on Cyber Security and Cloud Computing (CSCloud)/2022 IEEE 8th International Conference on Edge Computing and Scalable Cloud (EdgeCom)
Xiaofeng Chen, Lu Zhang, Yijian Zhang, Jingyi Du · 6 authors
Blockchain and Distributed Ledger Technology (DLT) are becoming important driving forces for a new round of scientific and technological development. The construction of blockchain information infrastructure has risen to a national strategic height. The industrial applications of Blockchain and DLT are developing and landing rapidly. At present, it has included many fields such as finance, government affairs and justice. At the same time, blockchain and DLT will have a far-reaching impact on international scientific, technological and economic development. For the healthy and orderly development of the blockchain and DLT industry, blockchain and DLT standards are being drafted, released and implemented one after another. This paper analyzes the current situation of international blockchain and DLT standardization and arranges the current situation of blockchain standardization working group in ISO. This paper introduces the organizational structure of ISO and the specific work of the working group, arranges all the blockchain related standards currently under development by ISO, and makes relevant analysis on the standard stage, standard content and standard classification; At the same time, it defines the direction of in-depth participation in ISO international standards and helps the development of international standardization of blockchain and DLT.
BACKGROUND: A clinical trial management system (CTMS) is a suite of specialized productivity tools that manage clinical trial processes from study planning to closeout. Using CTMSs has shown remarkable benefits in delivering efficient, auditable, and visualizable clinical trials. However, the current CTMS market is fragmented, and most CTMSs fail to meet expectations because of their inability to support key functions, such as inconsistencies in data captured across multiple sites. Blockchain technology, an emerging distributed ledger technology, is considered to potentially provide a holistic solution to current CTMS challenges by using its unique features, such as transparency, traceability, immutability, and security. OBJECTIVE: This study aimed to re-engineer the traditional CTMS by leveraging the unique properties of blockchain technology to create a secure, auditable, efficient, and generalizable CTMS. METHODS: A comprehensive, blockchain-based CTMS that spans all stages of clinical trials, including a sharable trial master file system; a fast recruitment and simplified enrollment system; a timely, secure, and consistent electronic data capture system; a reproducible data analytics system; and an efficient, traceable payment and reimbursement system, was designed and implemented using the Quorum blockchain. Compared with traditional blockchain technologies, such as Ethereum, Quorum blockchain offers higher transaction throughput and lowers transaction latency. Case studies on each application of the CTMS were conducted to assess the feasibility, scalability, stability, and efficiency of the proposed blockchain-based CTMS. RESULTS: A total of 21.6 million electronic data capture transactions were generated and successfully processed through blockchain, with an average of 335.4 transactions per second. Of the 6000 patients, 1145 were matched in 1.39 seconds using 10 recruitment criteria with an automated matching mechanism implemented by the smart contract. Key features, such as immutability, traceability, and stability, were also tested and empirically proven through case studies. CONCLUSIONS: This study proposed a comprehensive blockchain-based CTMS that covers all stages of the clinical trial process. Compared with our previous research, the proposed system showed an overall better performance. Our system design, implementation, and case studies demonstrated the potential of blockchain technology as a potential solution to CTMS challenges and its ability to perform more health care tasks.
May 1, 2022·2022 IEEE 8th Intl Conference on Big Data Security on Cloud (BigDataSecurity), IEEE Intl Conference on High Performance and Smart Computing, (HPSC) and IEEE Intl Conference on Intelligent Data and Security (IDS)
Blockchain is a decentralized distributed ledger where data is produced and stored in units of blocks, and is connected end to end in chronological order to form a chain structure. However, at present, the blockchain has a certain degree of closure, that is, the problem of interaction between the blockchain and the outside of the chain, and the blockchain cannot access the state of the external closed world system. In order to overcome this limitation, various platforms have introduced the concept of oracles in different forms and purposes. However, so far, there is still a lack of elaboration on the classification, analysis and research of basic Oracle methods. Based on the two basic perspectives of Oracle, this article studies and expresses the basic Oracle model of the blockchain to solve the following problems: From the perspective of the blockchain, the data flow is divided into inbound data flow and outbound data flow; From the perspective of the originator of the data flow, the communication direction is divided into push-based communication and pull-based communication. This paper describes the structural design of these four methods in detail, which can provide researchers with some method inspiration and design ideas for the interaction between the blockchain and the off-chain world.
Big Data and Digital Economy
Blockchain Technology Applications and Security
Physical Unclonable Functions (PUFs) and Hardware Security
May 1, 2022·2022 IEEE 8th Intl Conference on Big Data Security on Cloud (BigDataSecurity), IEEE Intl Conference on High Performance and Smart Computing, (HPSC) and IEEE Intl Conference on Intelligent Data and Security (IDS)
Smart contracts are distributed, self-executing programs on blockchain network and they have the potential to impact many industries. A large number of developers are optimistic about the development prospects of smart contracts. However, due to different levels of familiarity of developers with technology, the existence of serious vulnerabilities in code can result in huge property losses. The serious consequences of reentrancy vulnerabilities have attracted widespread attention from researchers, and researchers have proposed many approaches to detect them. Many experiments show that these approaches can only effectively detect certain types of vulnerabilities. Similar vulnerabilities still exist in some smart contracts. In this paper, we propose a semantic analysis-based detection method for reentrancy vulnerabilities. The method utilizes machine learning techniques to efficiently detect the vulnerabilities of the given code. And then, our method provides semantic analysis-based effective correction feedback of the code. Compared with the existing vulnerability detection tools Slither and Mythril, our method improves the work efficiency. Moreover, compared with the current Mythril method with the best vulnerability detection accuracy, our method improves the accuracy by 1.01%.
With the proliferation of pump-and-dump schemes (P&Ds) in the cryptocurrency market, it becomes imperative to detect such fraudulent activities in advance to alert potentially susceptible investors. In this paper, we focus on predicting the pump probability of all coins listed in the target exchange before a scheduled pump time, which we refer to as the target coin prediction task. Firstly, we conduct a comprehensive study of the latest 709 P&D events organized in Telegram from Jan. 2019 to Jan. 2022. Our empirical analysis reveals some interesting patterns of P&Ds, such as that pumped coins exhibit intra-channel homogeneity and inter-channel heterogeneity. Here channel refers a form of group in Telegram that is frequently used to coordinate P&D events. This observation inspires us to develop a novel sequence-based neural network, dubbed SNN, which encodes a channel's P&D event history into a sequence representation via the positional attention mechanism to enhance the prediction accuracy. Positional attention helps to extract useful information and alleviates noise, especially when the sequence length is long. Extensive experiments verify the effectiveness and generalizability of proposed methods. Additionally, we release the code and P&D dataset on GitHub: https://github.com/Bayi-Hu/Pump-and-Dump-Detection-on-Cryptocurrency, and regularly update the dataset.
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The development of education informatization is crucial to improve the quality of higher education and promote the innovation of education, thus to cultivate innovative talents that meet the requirements of the modern information society. However, the current education informatization construction still faces problems such as insufficient top-level design, unconnected data sharing, and risks of privacy leakage. To this end, this article combines the emerging blockchain technology to discuss the positive function of blockchain in the establishment of education informatization, the possible opportunities for education informatization in the future, and some important challenges that will be faced. Specifically, from the perspective of higher education information system, we analyze the crucial issues in the current information system architecture including postgraduate training, teaching management, supervisor management, project information management, etc., and present the security and scalability issues of the system. On this basis, we propose the potential solutions based on blockchain and analyze the positive effects brought by blockchain technology in terms of security protection and data sharing. Finally, we summarize several major future issues that still need to be overcome in the convergence of blockchain and informatization of higher education.
Because of its many advantages, big data has been extending to various domains of science, health, education, and commerce. Despite its many applications, big data sharing typically suffers from some key issues, such as user control, lack of incentives, cost, and the right of data. This paper proposes a decentralized big data sharing prototype to improve the applications and services of big data. The method makes use of Ethereum blockchain and related technologies to systematically recommend the implementation guidelines. The research provides a detailed description of the design and implementation of each sublayer of a big data system. As the method is based on blockchain technology, the key technical points are properly addressed in each of the layers. For evaluation, relevant data were collected, and functional testing was performed. A comparison was performed about the sharing frequency and blockchain consensus performance of similar platforms. The dual mining node of the proposed prototype succeeded in processing 1366 blocks and 300 messages. A comparatively satisfactory file access time in the range of 10 m to 20 s and file transmission time between 100 m and 200 s were achieved. The results obtained show that this prototype can effectively verify the feasibility of the model, the layered architecture, and the related sharing mechanism. For the functional and performance testing, practical projects were implemented and evaluated. The promising results obtained testify that the research offers a theoretical background for innovative research in the domain and specialized guidelines for practical implementation.
Thiago Bulhões da Silva Costa, Lucas Shinoda, Ramon A. Moreno, José Eduardo Krieger · 5 authors
Background The importance of blockchain-based architectures for personal health record (PHR) lies in the fact that they are thought and developed to allow patients to control and at least partly collect their health data. Ideally, these systems should provide the full control of such data to the respective owner. In spite of this importance, most of the works focus more on describing how blockchain models can be used in a PHR scenario rather than whether these models are in fact feasible and robust enough to support a large number of users. Objective To achieve a consistent, reproducible, and comparable PHR system, we build a novel ledger-oriented architecture out of a permissioned distributed network, providing patients with a manner to securely collect, store, share, and manage their health data. We also emphasize the importance of suitable ledgers and smart contracts to operate the blockchain network as well as discuss the necessity of standardizing evaluation metrics to compare related (net)works. Methods We adopted the Hyperledger Fabric platform to implement our blockchain-based architecture design and the Hyperledger Caliper framework to provide a detailed assessment of our system: first, under workload, ranging from 100 to 2500 simultaneous record submissions, and second, increasing the network size from 3 to 13 peers. In both experiments, we used throughput and average latency as the primary metrics. We also created a health database, a cryptographic unit, and a server to complement the blockchain network. Results With a 3-peer network, smart contracts that write on the ledger have throughputs, measured in transactions per second (tps) in an order of magnitude close to 102 tps, while those contracts that only read have rates close to 103 tps. Smart contracts that write also have latencies, measured in seconds, in an order of magnitude close to 101 seconds, while that only read have delays close to 100 seconds. In particular, smart contracts that retrieve, list, and view history have throughputs varying, respectively, from 1100 tps to 1300 tps, 650 tps to 750 tps, and 850 tps to 950 tps, impacting the overall system response if they are equally requested under the same workload. Varying the network size and applying an equal fixed load, in turn, writing throughputs go from 102 tps to 101 tps and latencies go from 101 seconds to 102 seconds, while reading ones maintain similar values. Conclusions To the best of our knowledge, we are the first to evaluate, using Hyperledger Caliper, the performance of a PHR blockchain architecture and the first to evaluate each smart contract separately. Nevertheless, blockchain systems achieve performances far below what the traditional distributed databases achieve, indicating that the assessment of blockchain solutions for PHR is a major concern to be addressed before putting them into a real production.
Bo Zhao, Chenhan Shangguan, Xiaoyan PENG, Yang AN · 6 authors
In order to solve the problems of low detection accuracy and high false positive rate of traditional smart contract vulnerability detection methods and less consideration of bytecode level smart contract features in neural networks, a smart contract bytecode vulnerability detection method based on semantic perception graph neural network was proposed. First, in order to generate the control flow graph, the basic blocks divided by the smart contract bytecode were used as the nodes, and the call relationship between the basic blocks was extracted from the bytecode as the edges. Then, control flow graph is transmitted into the graph convolutional network for training to obtain the feature representation of the graph nodes; Afterwards, the contract bytecode instruction sequence is segmented, transformed into a word vector, embedded into a low-dimensional space and transmitted to a long short-term memory network for training. Then, the vector representation of bytecode semantic information was obtained. Finally, the generated node features and semantic features were spliced and transmitted to the full connection layer for dimensionality reduction. Combined with semantic information and node features, the vulnerability detection was carried out for smart contracts. The real smart contracts in public dataset were used for training and testing, and verified in two types of vulnerability classification datasets through traditional methods and artificial tags. The method proposed in this paper was compared with three traditional smart contract vulnerability detection tools and one smart contract vulnerability detection method based on neural network. The experimental results showed that the proposed network greatly improves the performance of network in terms of various indicators, and detects the contracts with vulnerabilities which are not detected by the other four methods. It shows that adding the bytecode semantic information to graph neural network can effectively improve the detection accuracy and reduce the false alarm rate.
Based on blockchain technology,Ethereum Solidity smart contract as a computer protocol is designed to spread,verify,or execute contracts in an informative way,and it provides a foundation for various distributed application services.Although implemented for less than six years,its security problems have frequently broken out and caused substantial financial losses,which attracts more attention in the security inspection research.This paper firstly introduces some specific mechanisms and operating principles of smart contracts based on Ethereum related techniques,and analyzes some smart contract vulnerabilities occurring frequently and deriving from the characteristics of smart contracts.Then,this paper explains the traditional mainstream smart contract vulnerability detecting tools in terms of symbolic execution,fuzzing,formal verification,and taint analysis.In addition,in order to cope with the endless new vulnerabilities and the need to improve the efficiency of detection,vulnerabilities detection based on machine learning in recent years is classified and summarized according to the various ways of problem transformation in three perspectives including text processing,non-Euclidean graph and standard image.Finally,this paper proposes to formulate more extensive and accurate standardized information database and measurement indicators towards the insufficiency of the detection methods in two directions.