【Abstract】We study the use of platform-specific tradable cryptographic tokens to solve the coordination problemthat is common in adopting newmarketplaces. We show that certain characteristics of platform-specific tokens-specifically, their tradability, the ability of the platform to commit both to accept and to require these tokens in the future, and the ability to commit to a price and/or quantity schedule-can help overcome the coordination problem and can support equilibria favorable to the new marketplace. Compared with other mechanisms in the literature to address the coordination problem-such as subsidies of early users and promises of refunds or buybacks if the platform fails-platform-specific cryptographic tokens are less likely to favor established or larger firms with established reputations and financial resources. We find that tokens allow a marketplace to trade off future revenue for present revenue, which then can be used to address the coordination problem. On the other hand, the ability to trade out of the platform results in a smaller future network and lower total profit. Thus, if the new marketplace is not facing capital constraints, then the most profitable strategy is the traditional strategy to subsidize adoption. If the new marketplace is capital-constrained, however, as is often the case for new entrants and unproven technology applications, tokens can offer an alternative that is increasingly attractive as the cost of capital increases.
【Abstract】Emerging technologies such as blockchain have accelerated the digitization of a variety of industries, improved the operational efficiency of enterprises, and promoted in-depth integration of digital technology with the real economy. Blockchain has characteristics that include distributed storage, peer-to-peer transmission, strong confidentiality, and easy traceability. This article introduces blockchain into an enterprise's information management system with the aim of breaking the enterprise's digital barriers by using technologies such as distributed ledgers, smart contracts, and asymmetric encryption, thus improving the security and applicability of the enterprise data assets. This article explores the characteristics and security of three types of blockchain in depth, designs the model framework of the blockchain digital system (BDS) based on industry needs, and analyzes the functions and the operating mechanisms of each level of the system in detail. Finally, based on the characteristics of public blockchain, consortium blockchain, and private blockchain, three typical application scenarios in which the BDS can be used are selected, and the article discusses how E-retail supply chains, virtual power plants, and carbon trading platforms can realize digital management using the BDS, thus providing a practical basis for construction and application of the BDS.
【Abstract】Recently, blockchain has increasingly been used in several sectors as the technological underpinning for providing a secure and reliable environment. It has been used in a few sectors for provenance of high-value products. In this paper, we focus on the pharmaceutical sector in which the need for drug provenance is crucial due to counterfeiting and for finding efficient ways to handle drug waste. The focus on this paper is two-fold. The first contribution is to review the existing literature critically and systematically on blockchain use in the pharmaceutical sector. We identify four crucial factors that are critical in the pharmaceutical sector. Subsequently, we systematically review the existing literature on blockchain use in the pharmaceutical sector. The second contribution is based on the analysis of the existing literature, we identify key research gaps on blockchain use in the pharmaceutical sector. Finally, an intelligent platform is proposed to address the identified gaps.
【Abstract】Various businesses and industries such as financial, medical care management, supply chain management, data management, Internet of Things (IoT) and government supremacy, have been using blockchain technology to develop systems. During the selection of blockchain platforms, many criteria need to be taken into account depending on the organization, project and use case requirements. This study proposes a systematic selection method based on the Fuzzy AHP-TOPSIS approach which compares and selects alternative blockchain platforms against a set of selection criteria that cover both features and non-functional properties. A case study was conducted to evaluate the applicability of the proposed selection method. The proposed selection method which consists of three main stages was applied for the comparison and selection of the most appropriate blockchain platform for two projects. In the case study, three blockchain platforms were selected and ranked for each project based on selection criteria derived from the project requirements. Both project representatives showed strong agreement with the applicability aspects of the proposed selection method. It is concluded that the proposed selection criteria and selection method can be applied practically to support the decision-makers in blockchain platform selection for real-world projects.
【Abstract】Internet of Things (IoT) devices generate a massive amount of data on a regular basis. This data has the potential to revolutionize every sector by developing intelligent systems. Unfortunately, the data is inaccessible due to privacy concerns. A decentralized machine learning approach, i.e., Federated Learning (FL), enables clients to train models locally in an iterative and collaborative manner. However, some clients may not be able to fully participate in training due to limited computational resources. To address the aforementioned issues, we propose Block-FeST, a blockchain-based Federated-Split Learning framework for anomaly detection using Transformers, that incorporates the strength of Federated and Split Learning (FSL). FL is employed to mitigate data privacy issues, while Split Learning (SL) is used to offload some computational overhead from constrained clients to a central server. Block-FeST is also capable of training a transformer model, which we demonstrate in the context of a temporal anomaly detection (AD) problem. Moreover, the use of a blockchain will generate an audit trail that can be used to address any challenges from the customers to take corrective actions. We have implemented our proposed solution and compared it against known centralized and decentralized baselines. Block-FeST achieves an accuracy of 86%, which is competitive with the other solutions, while providing additional benefits in terms of decentralization and client-side offloading.
【Abstract】Innovative uses of the blockchain technology in existing business models open up new opportunities to improve services and applications with new attributes such as integrity, transparency and auditability. In many cases, however, this involves a collaboration of different companies and entities, and therefore the integration with a blockchain depends on a good relationship between all parties. A key step in that direction is defining a governance both for the consortium that undertakes the service or application and for its wider business ecosystem. Thus, the governance must cover not only management aspects of the network, but also processes that regulate the application and the relationship between participants. This paper discusses the case study of a traceability service for animal protein supply chain, which has strengthened its value proposition by means of a new blockchain layer. A framework to facilitate the tailoring of its governance is proposed and discussed.
【Abstract】In the article, we study the horizontal scaling of the Waterfall or similar blockDAG networks by partitioning them into subnetworks by applying hierarchical and graph-based clustering algorithms. It leads to the reducing the network load and, in addition, to the increasing of the potential performance parameters of the underlying protocol. We consider methods of topology construction, propose clustering algorithms, and perform a simulation of a network partitioning into subnetworks.
【Abstract】Privacy and integrity preservation of user data is a major challenge in the context of location based services, as the assumption of trusted relationship between the user and the service provider might be too strong. The question is: how to securely collect, store and process position, navigation and timing (PNT) information and/or georeferenced data, assuming that the service provider cannot be trusted? In this work, we propose an architecture that enables LBS with privacy and integrity in untrusted environments, leveraging blockchain and secure computation. We provide mechanisms for sharing and processing PNT information and/or georeferenced data, with a detailed description of the employed cryptographic schemes and algorithms. Furthermore, we provide a validation of the proposed architecture by means of an emulation-based testbed.
【Abstract】We survey literature that combines blockchain and semantic technologies. Our findings identify main areas where the combination of blockchain with semantic technologies are considered, and answer key research questions, surveying existing challenges addressed, their advantages, technical perspectives, and future recommendations.
【Abstract】Dynamic Spectrum Sharing (DSS) is proposed as a solution to the spectrum scarcity and under-utilization problem in a world of ever-increasing spectrum demand. Enabling DSS, however, requires overcoming many technical, regulatory, and economic challenges. Cognitive Radio (CR) provided a solution for some of the technical issues of DSS by equipping wireless devices with intelligent sensing and decision making capabilities to enable dynamic sharing of the surrounding spectrum between devices. However, CR alone has been unable to provide a fully dynamic ecosystem for spectrum sharing that guarantees protection for spectrum owners. This has led multiple spectrum regulators to implement frameworks that enable DSS through a centralized spectrum management system that complements the CR capabilities to ensure compliance with spectrum access policies and regulations. However, these frameworks require trusting a third party to manage spectrum access and do not provide intrinsic mechanisms to incentives spectrum owners to share their spectrum. Blockchain technology provides a distributed platform for autonomous asset trading that can be utilized to implement a fully dynamic spectrum sharing system, ensuring transparency and trust between devices without the need for a third party. This paper provides a blockchain-based model for a DSS that represents spectrum access rights as tokenized assets and enables trading of these spectrum tokens between multiple users on a distributed ledger using smart contracts. The proposed model is implemented using Hyperledger Fabric (HLF) as a permissioned blockchain network and the details of the implemented Chaincode transactions are outlined.
【Abstract】Synchronized aggregate signature is a special type of signature that all signers have a synchronized time period and allows aggregating signatures which are generated in the same period. This signature has a wide range of applications for systems that have a natural reporting period such as log and sensor data, or blockchain protocol. In CT-RSA 2016, Pointcheval and Sanders proposed the new randomizable signature scheme. Since this signature scheme is based on type-3 pairing, this signature achieves a short signature size and efficient signature verification. In this paper, we design the Pointchcval-Sanders signature-based synchronized aggregate signature scheme and prove its security under the generalized Pointcheval-Sanders assumption in the random oracle model. Our scheme offers the most efficient aggregate signature verification among synchronized aggregate signature schemes based on bilinear groups.
【Abstract】Internet of Things (IoT) systems have started becoming a part of our daily lives in our homes, hospitals, offices, and other settings. As the use of IoT devices continues to grow, the need for effective security and privacy solutions becomes important. In situations where multiple users need to interact with an IoT device or system, it is essential to have a secure and flexible approach to controlling access. One potential solution is to use Blockchain-based technologies, such as Non-Fungible Tokens (NFTs), to provide secure and flexible access control. NFTs can serve as untamperable keys that allow access only to individuals who have been added as team members. This approach can help to prevent unauthorized access and to ensure that only authorized individuals can interact with the device. In addition, successful implementation of this approach across the IoT domain requires that the software is executable even on resource-constrained devices. In this paper, we present our approach that uses NFTs to control access to IoT devices. We demonstrate how this approach can be used to allow only authorized individuals to access the device, add new users to the device's access list, and prevent unauthorized access. We also conduct an experimental study using ESP32 microcontrollers and Raspberry Pi to evaluate the performance of our approach. We find that the computational power required and the associated delays are within a few milliseconds, making this approach suitable for use even on resource-constrained devices. Overall, our results suggest that using NFTs for access control can provide a secure and flexible solution for IoT systems.
【Abstract】The IoT market is continuously expanding, and security measures parallel to the growing industrialization has drawn the research community's attention. While several works have focused on the different technologies used to protect IoT devices, this paper aims to narrow the focus to Blockchain and Artificial Intelligence (AI) solutions for security and privacy issues faced by these devices. These technologies address two major vulnerabilities with edge devices on IoT networks: centralization and weak edge nodes. Blockchain provides a distributed system that can help avoid a single-point failure and can be used to optimize battery life on low-level devices by load balancing. On the other hand, AI's power to learn and adapt is critical to automate systems and make them intelligent enough to analyze collected data. The combination of these two technologies is capable of mitigating multiple challenges IoT architectures face currently. The paper discusses the latest major architectures that integrate Blockchain and AI to enhance security within the. This paper also presents the comprehensive take on the device security and drawbacks to these mechanisms. This work also addresses the future of security in IoT and suggests different areas that need further work to better comprehend how the combination of these technologies can assist in enhancing security.
【Abstract】This paper explores the potential of blockchain technology to improve cross-border trade by providing a secure and transparent way to track and verify the movement of goods, services, and funds across borders. By creating a tamper-proof record of transactions, blockchain can reduce fraud and increase transparency in the supply chain, as well as streamline the process of documenting and verifying transactions. The paper presents a new technology proposal, developed by Cobe, for a comprehensive cross-border trade ecosystem that includes both native permissioned and permissionless chains, connected via a relay system, and featuring a suite of cross-border trade APIs. The study also examines the concurrency protocols in the context of the proposed dual-sided blockchain architecture, providing a comprehensive analysis of the proposed system's potential to improve cross-border trade.
【Abstract】The proliferation of digital technologies and the ubiquitous nature of data connectivity has dramatically increased the landscape of cyberattacks over the past decade. Ransomware attacks have become a global incidence and the most destructive cyber menace. As a popular example of cryptovirology, ransomware attacks typically encrypt files on a target computer and threaten to publish or permanently prevent access to the victim's data unless a ransom is paid. In general, ransom demands are often made in cryptocurrency to obscure transactions and maintain anonymity. Nonetheless, paying the ransom does not guarantee data recovery; and therefore, there is a strong need to develop alternative data recovery strategies. To build and implement proper data recovery procedures, it is necessary to analyze ransomware and identify its characteristics. In this paper, we first provide a review of ransomware types and common data recovery methods. Then, we propose a novel ransomware detection and data recovery framework to effectively retrieve data from infected files. Specifically, we investigate the notorious WannaCry malware and analyze its execution on a Windows virtual machine. We conduct digital forensics using the Autopsy tool to recover WannaCry-infected data and demonstrate the practicality of the proposed framework. Our framework can be applied to develop effective data recovery methods for WannaCry and other ransomware variants with similar behavior.
【Abstract】For permissionless blockchains, scalability is paramount. While current technologies still fail to address this problem fully, many research works propose sharding or other techniques that extensively adopt parallel processing of transactions. In these approaches, a potentially large number of committees of nodes independently perform consensus and process new transactions. Hence, in addition to regular intra-committee communication, (1) new transactions have to be delivered to the right committee, (2) committees need to communicate to process inter-shard transactions or (3) to exchange intermediate results. To contrast slowly adaptive adversaries, committees should be frequently changed. However, efficient communication to frequently-changing committees is hard. We propose a simple approach that allows us to implicitly select committee members and effectively deliver messages to all members of a specific committee, even when committees are changed frequently. The aim of our design is to provide a committee selection procedure and a committee-targeted communication primitive to be applied in most of the scalable blockchain architectures that are currently proposed in literature. We provide a theoretical proof of the security of our approach and first experimental results that shows that our approach might be feasible in practice.
【Abstract】Blockchain-based non-terrestrial networks (NTN) are expected to ensure the reliability of data in the process of data sharing between untrusted entities. Nevertheless, the low transactions per second (TPS) of blockchain makes it unable to support a large number of data sharing tasks in NTN. One of the key factors for low TPS is the single-chain structure of blockchain. In this way, block generation and block verification are only permitted to be executed sequentially, that means only a single valid block can be generated in the same period. To resolve this dilemma, we propose a twin-chain practical byzantine fault tolerance consensus strategy (TPBFT), in which the consensus process is executed in parallel at two aspects. The first parallel aspect permits block generation and block verification being executed in parallel by twin-chain structure. The second parallel aspect is that the block can be generated with sub-blocks being generated in parallel by replacing transactions with sub-blocks. Finally, the effectiveness of TPBFT is verified by simulation, and the TPS can reach up to 3 x 10(9), which means the problem of low TPS of blockchain-based NTN is solved.
【Abstract】Blockchain technology has been integrated into diverse software applications by enabling a decentralised architecture design. However, the defects of on-chain algorithmic mechanisms, and tedious disputes and debates in off-chain communities may affect the operation of blockchain systems. Accordingly, blockchain governance has received great interest for supporting the design, use, and maintenance of blockchain systems, hence improving the overall trustworthiness. Although much effort has been put into this research topic, there is a distinct lack of consideration for blockchain governance from the perspective of software architecture design. In this study, we propose a pattern-oriented reference architecture for governance-driven blockchain systems, which can provide guidance for future blockchain architecture design. We design the reference architecture based on an extensive review of architectural patterns for blockchain governance in academic literature and industry implementation. The reference architecture consists of four layers. We demonstrate the components in each layer, annotating with the identified patterns. A qualitative analysis of mapping two concrete blockchain architectures, Polkadot and Quorum, on the reference architecture is conducted, to evaluate the correctness and utility of proposed reference architecture.
【摘要】为解决网络安全性、数据可靠性及用户隐私性三大物联网(internet of things, IoT)可信要素问题，利用区块链技术构建泛在可信物联网系统，提出一种面向泛在可信物联网的区块链体系架构。该架构通过分层架构与跨层协同方式，有望突破区块链不可能三角限制，解决区块链技术应用于泛在可信物联网中协议机制不匹配等问题。
