Blockchain Papers

Rabiya Khalid, Muhammad Waseem Malik, Turki Ali Alghamdi, Nadeem Javaid

No abstract is available for this record.

Esteban Romero‐Frías, Francisco Luis Benítez-Martínez, Pedro Núñez-Cacho Utrilla, Valentín Molina Moreno

No abstract is available for this record.

Yiming Wu, Gehao Lu, Na Jin, LiYu Fu · 5 authors

The fog platform is very suitable for time and location sensitive applications. Compared with cloud computing, fog computing faces new security and privacy challenges. This paper integrates blockchain nodes with fog nodes, and uses multi-party secure computing (MPC) in smart contracts to realize privacy-protected fog computing. MPC technology realizes encrypted input and output, so that participants can only get the output value of their own function. It is impossible to know the input and output of other people, and privacy calculation is realized. At the same time, the blockchain can perform network-wide verification and consensus on the results calculated by the MPC under the chain. Ensure the reliability of the calculation results. Due to the integration of blockchain and fog nodes, access control and encryption are guaranteed, integrity and isolation are provided, and privacy-sensitive data is controlled. As more complex topological structures emerge, the entire chain of fog nodes must be trusted. This ensures the network security of distributed data storage and network topology, users and fog service providers. Finally, trusted fog computing with privacy protection is realized.

Junaid Ahmed Khan, Kavyashree Umesh Bangalore, Abdullah Kurkcu, Kaan Özbay

Trajectory data from connected vehicles (CVs) and other micromobility sources such as e-scooters, bikes, and pedestrians is important for researchers, policy makers, and other stakeholders for leveraging the location, speed, and heading, along with other mobility data, to improve safety and bolster technology development toward innovative location-based applications for citizens. Such raw data needs to be stored and accessed from a non-proprietary database while the obfuscation and encryption techniques on current cloud-based proprietary solutions incur data losses that are deemed inefficient for accurate usage, particularly in time-sensitive real-time operations. In this paper, we target the problem of scalably storing and retrieving potentially sensitive data generated by vehicles and propose TREAD, a blockchain-based system comprising smart contracts to store this mobility data on a distributed ledger such that multiple peers can access and utilize it in different location-based applications while not revealing users’ sensitive personal information. It is, however, challenging to scalably store large amounts of constantly generated trajectories, and to achieve scalability we leverage InterPlanetary File System (IPFS), a scalable distributed peer-to-peer data storage system. To avoid users injecting malicious/fake trajectories into the ledger, we develop efficient consensus algorithms for the stakeholders to validate the storage and retrieval process in a distributed manner. We implemented TREAD on the open-source Hyperledger Fabric blockchain platform using trajectory data generated for 700 vehicles in a simulation environment well calibrated with vehicle trajectories from a real-world test-bed in New York City. Results show that TREAD scalably stores trajectory data with lower delay and overhead.

Xiaohui Zhang, Xianghua Miao

Consortium blockchain-based A-CDM (Airport Collaborative Decision Making) was a decentralized technology solution proposed by some researchers in recent years to solve robustness, privacy, and security issues in the traditional centralized architecture. The key idea of blockchain-based A-CDM is to use blockchain technology to store the flight operation data in a distributed, consistent, and tamper-proof ledger, further improve the capability of flight management and reduce the trust barriers among the multi-stakeholders such as airport, air traffic management bureau, airlines, and ground service agency, etc. The RAFT consensus was adopted in many blockchain-based data sharing solutions to meet the need for efficiency in data transmission. However, the RAFT algorithm can only be used in a non-byzantine network because security requirements such as preventing malicious nodes are not fully considered. It will bring an immeasurable impact on flight operation when the leader node of RAFT-based A-CDM was caused by malicious control. In response to the above problems, this paper proposes an optimization scheme to improve the security performance of the consortium blockchain in A-CDM.

Diego Romano, Giovanni Schmid

In the last four years, the evolution and adoption of blockchain and, more generally, distributed ledger systems have shown the affirmation of many concepts and models with significant differences in system governance and suitable applications. This work aims to analyze distributed ledger technology (DLT) critically. Starting from the topical idea of decentralization, we introduce concepts and building blocks currently adopted in the available systems centering on their functional aspects and impact on possible applications. We present some conceptual framing tools helpful in the application context: a DLT reference architecture, off-chain and on-chain governance models, and classification of consensus protocols. Finally, we introduce the concept of process authenticity, reviewing tools and strategies for integrating DLT with the physical world and proposing a constructive scheme for the authentication of a physical resource through alphanumeric data.

Naram Mhaisen, Mhd Saria Allahham, Amr Mohamed, Aiman Erbad · 5 authors

Service provisioning systems assign users to service providers according to allocation criteria that strike an optimal trade-off between users’ Quality of Experience (QoE) and the operation cost endured by providers. These systems have been leveraging Smart Contracts (SCs) to add trust and transparency to their criteria. However, deploying fixed allocation criteria in SCs does not necessarily lead to the best performance over time since the blockchain participants join and leave flexibly, and their load varies with time, making the original allocation sub-optimal. Furthermore, updating the criteria manually at every variation in the blockchain jeopardizes the autonomous and independent execution promised by SCs. Thus, we propose a set of light-weight agents for SCs that are capable of optimizing the performance. We also propose using online learning SCs, empowered by Deep Reinforcement Learning (DRL) agent, that leverage the chained data to continuously self-tune its allocation criteria. We show that the proposed learning-assisted method achieves superior performance on the combinatorial multi-stage allocation problem while still being executable in real-time. We also compare the proposed approach with standard heuristics as well as planning methods. Results show a significant performance advantage over heuristics and better adaptability to the dynamic nature of blockchain networks.

Zeinab Shahbazi, Yung-Cheol Byun

One of the common transportation systems in Korea is calling taxis through online applications, which is more convenient for passengers and drivers in the modern area. However, the driver's passenger taxi request can be rejected based on the driver's location and distance. Therefore, there is a need to specify driver's acceptance and rejection of the received request. The security of this system is another main core to save the transaction information and safety of passengers and drivers. In this study, the origin and destination of the Jeju island South Korea were captured from T-map and processed based on machine learning decision tree and XGBoost techniques. The blockchain framework is implemented in the Hyperledger Fabric platform. The experimental results represent the features of socio-economic. The cross-validation was accomplished. Distance is another factor for the taxi trip, which in total trip in midnight is quite shorter. This process presents the successful matching of ride-hailing taxi services with the specialty of distance, the trip request, and safety based on the total city measurement.

Hema Pallevada, Gayathri Phani Kumar Kanuri, Sravani Posina, Satyendra Paruchuri · 5 authors

Online vehicle booking service became a growing need now-a-days as it offers an efficient and cheaper alternative. One can directly call a taxi to any location at any time they want without the need for a lengthy delay. There are various platforms implementing online vehicle booking service but the major issue with them is having a centralized authority which are pocketing huge profits. A fixed percentage of money paid by the user is taken by the centralized authority. These centralized systems also tend to misuse their user’s data and are also prone to several attacks. One of the best solutions to this problem is to use BlockChain. Our objective is to avoid this centralized authority by creating a decentralized application. Not just removing the central authority, BlockChain also provides several features like immutability, better transparency, enhanced security and traceability. Platforms like Ethereum and Hyperledger allow one to develop decentralized applications and deploy them in the blockchain. Smart Contracts can be developed using Solidity to achieve decentralization. This maintains transparency, immutability and removes a central authority which may misuse its user's information.

Felipe Desiglo Ferrare, Derick Moreira Baum, Jorge Rady de Almeida, João Batista Camargo · 5 authors

Electric Vertical Take-Off and Landing (eVTOL) has been used in the most diverse applications, as electric vehicles and having a small size, they could land in small spaces and maybe in dense urban areas. Another type of vehicle used is the Unmanned air vehicle (UAV), which doesn't need user (human) control. The future of the development of this technology is the use of these vehicles to make deliveries and transportation of people and many others, having many vehicles making transit in small areas, leading to traffic jams. Despite this, most research focuses on scenarios with only one or a few agents. These scenarios, however, do not reflect the reality expected in the future, including multiple aircraft controlled by different entities, with diverse goals. These scenarios, mainly urban and used in dense areas, with many vehicles having to share the same air space, the normal Air Traffic Management (ATM) could not handle this new traffic, of hundreds of small and autonomous vehicles, in a central city region, this requires specific rules that have been called UAM (Urban Air Mobility). Bringing issues as safety and rules regarding the organization of this new system. This work aims to present scenarios using computer simulations created based on a multi-agent simulation tool or a Multi-Agent System (MAS). The MAS has the advantage that we could create and simulate more powerfully the existence of multiple vehicles (or agents) that act independently, as would happen in a real situation. This tool uses the Netlogo language and allows the modeling of multiple UAVs with stochastic trajectories created in a decentralized way, verifying how the model deals with conflicts and obstacles, highlighting some challenges and capabilities of UAM. Presenting some scenarios, using different parameters, such as aircraft by distinct capacities and in adverse climatic situations. As well, analyzes of results from these simulations conducted to assess the safety and the performance of the process. Using this tool, we propose some testing scenarios and execute some validation using multiple executions with different parameters as the number of planes and velocity to get results as the trajectory time and the number of conflicts. With this data, we try to show that we could estimate the airspace capacity and validate the safety of the given model used parameters. We will show some results of the execution of this tool and try to make some inferences and draw some conclusions based on these results.

Giuseppe Loseto, Filippo Gramegna, Saverio Ieva, Agnese Pinto · 6 authors

No abstract is available for this record.

Jinjin Zhang, Xin Li, Yong‐Hong Kuo, Yan Chen

This paper considers an online retailer and his or her manufacturer, both facing financial constraints and wishing to get loans from their e-commerce platform-backed finance company. Based on shared transaction data and monitored sales accounts, a tripartite loan contract is proposed to coordinate three parties’ actions in this supply chain financing problem. We prove that the proposed loan contract aligns the decentralized decision-makings of each party and duplicates the optimal channel performance under a fully integrated decision-making framework. A case study is then conducted to illustrate the performance of the proposed loan contract. The result shows that the proposed loan contract outperforms wholesale-price contracts, where coordination does not take place, and buyback contracts, where coordination happens between the retailer and the manufacturer only. Furthermore, a sensitivity analysis reveals that profit allocations among the lender, the retailer, and the manufacturer resulted from the proposed loan contract are more balanced when the cost-to-retail ratio or risk premium is high.

Indranil Sarker, Bidisha Datta

No abstract is available for this record.

Yan Li, Ming K. Lim, Chao Wang

No abstract is available for this record.

Hansjörg Albrecher, Dina Finger, Pierre-Olivier Goffard

The resource-consuming mining of blocks on a blockchain equipped with a proof of work consensus protocol bears the risk of ruin, namely when the operational costs for the mining exceed the received rewards. In this paper we investigate to what extent it is of interest to join a mining pool that reduces the variance of the return of a miner for a specified cost for participation. Using methodology from ruin theory and risk sharing in insurance, we quantitatively study the effects of pooling in this context and derive several explicit formulas for quantities of interest. The results are illustrated in numerical examples for parameters of practical relevance.

Yimin Yu, Chuanjia Yao, Yi Zhang, Rong Jiang

At present, the world economy is in recession, especially under the impact of the Covid-19 epidemic, China's economy has also been greatly impacted. In this context, the disposable personal income of residents has also declined to varying degrees. More and more people choose economical life. If they can buy a used car in good condition at a good price, they are less likely to buy a brand new one. Under such a consumption concept, China's demand for second-hand cars is increasing. However, although China's second-hand car industry has developed for more than 30 years and the market scale has gradually expanded, there are still many problems behind the prosperity of the second-hand car market. These problems have existed for a long time, leading to a lot of disputes, unhappiness, disappointment, and even threats to the lives of consumers. These long-term problems also affect the virtuous circle of the second-hand car market, and hinder the healthy development of China's economy to a certain extent. In the past, research work mainly focused on the role of new policies, relevant laws and vehicle management and traffic management functions, this paper introduces the blockchain technology, which has the advantages of non tampering, transparency and traceability. This paper attempts to use blockchain technology as an auxiliary means to solve the long-standing problems in the used car market. This paper proposes a framework of used car trading based on blockchain in cloud service environment, and explains the working principle of the framework. Finally, the future research work is prospected.

Liming Xu, Stephen Mak, Alexandra Brintrup

No abstract is available for this record.

Xiutian Shi, Shuning Yao, Suyuan Luo

With the development of ecommerce and digital technologies, we have witnessed a boom of platform operations. Amid their strong growth prospects, it is observed that platforms have created controversial issues and challenges, which could be potentially solved by the combination of blockchain features. More and more studies exploring the implementation of blockchain in platform operations have appeared in recent years. In this paper, motivated by the industrial practices of different types of product selling and service platforms, we first conduct a holistic literature review of the most representative papers relevant to platform operations. Examining the value of different blockchain features in operations management field, we further review the related works on platform operations with blockchain technologies. Afterwards, we analyse the innovative applications and challenges in platforms such as physical and virtual product selling platforms, rental/sharing and on-demand service platforms. A future research agenda is established which lays the solid foundation for further studies on platform operations in the blockchain era.

Yuze Li, Shangrong Jiang, Jianming Shi, Yunjie Wei

No abstract is available for this record.

Zhiming Zhang, Da Ren, Yanfei Lan, Shanxue Yang

No abstract is available for this record.

Gustavo A. Oliva, Ahmed E. Hassan

Ethereum is the most popular blockchain platform for the development of blockchain-powered applications (a.k.a, ). Developing a involves translating requests captured in the frontend of an application into contract transactions. However, transactions need to be payed for. Ethereum employs the gas system to charge transaction fees. The gas system has three key components, namely gas price, gas usage, and gas limit. We refer to these components and their interplay as the gas triangle. In this paper, we claim that the inherently complex gas triangle should not be exposed to end-users. We conduct two studies that provide empirical evidence to support our claim. In light of our results, we provide a list of recommendations to novice end-users. We conclude the paper with a list of research challenges that need to be tackled in order to support the development of next-generation that completely hide the gas triangle from end-users.

Søren F. Mortensen

The financial markets industry has for a long time experimented with blockchain technology and developed many use cases which the market participants over many years have tested the technology against. While there have been many projects, the broader adoption of blockchain has yet to materialise in financial markets. Other industries, notably supply chain, have successfully rolled out global blockchain networks and are seeing the benefits of this technology at a larger scale. The failure of many projects has been down to a set of common factors, for example, the lack of a solid business case or the effort required to align consortium partners to a common goal with a new network. The emergence of digital assets and central bank digital currencies (CBDCs) could be seen to be the catalysts for blockchain on a wider scale in financial markets. They have the potential to disrupt financial markets and especially post-trade as we know it today. Almost 80 per cent of central banks are experimenting with CBDC, and it is just a matter of time before this goes mainstream. Established financial institutions must adapt to this in order to face the threat from new market entrants, and the ecosystems that are being created or face disintermediation.

Yinglei Teng, Yuanyuan Cao, Mengting Liu, F. Richard Yu · 5 authors

While the vehicular network enables geographically distributed cooperative computation, its mature implementation has long been constrained due to the lack of an effective management platform. In this paper, employing the security and privacy attributes of blockchain, we propose a novel Blockchain-enabled Large-scale Parked Vehicular Computing (BLPVC) architecture to utilize the potential solar energy and vehicular computational resources in the outdoor parking lot. However, the uneven green power supply and random arrival time of electric vehicles compose the highly complex environment. Accordingly, in this paper, to handle the efficient utilization of the distributed resources by blockchain technology, we propose an integrated optimization framework which leverages the green energy utilization and service latency limit among the processes of block generation, task computing, and communication, whereas such a design leads to the mixed-timescale stochastic optimization problem. To this end, corresponding to the dynamic solar energy arrival, we propose a shaped deep deterministic policy gradient (DDPG) algorithm to accelerate the learning rate of computational frequency control in the short-term stage; while in the long-term stage, for the mixed-integer programming (MIP) of task offloading and blockchain parameters adjustment, a series of transformation is employed to preserve convexity. Finally, experiments are carried out on Python demonstrating that the proposed scheme achieves a balanced performance between service latency and distributed resources, while the battery depreciation cost is heavily reduced.

Rongbo Zhu, Hao Liu, Xiaozhu Liu, Shaohua Wan · 5 authors

Internet of vehicles (IoV) enables a large number of applications for consumers by integrating massive electronics, which aggravates the spectrum scarcity and data security, and degrades the quality of services (QoS) and experiences of consumers obviously. Focusing on enhancing the security and improving spectrum utilization, this article proposes a contract-theory-based secure spectrum sharing framework, which adopts the consortium blockchain to guarantee security of spectrum sharing and utilizes the practical Byzantine fault tolerant consensus algorithm to achieve consensus in IoV. Smart contracts are then formed based on insurance contracts to promote primary users to share their idle spectrum resources. A preference-based spectrum allocation algorithm is designed to maximize the total utility of secondary users (SUs). Simulation results show that, compared with the existing schemes, the proposed scheme achieves better performance in terms of the utility of SUs and the spectrum utilization greatly, which provides more access opportunities to consumers in IoV.