Eric Masanet, Arman Shehabi, Nuoa Lei, Harald Vranken · 6 authors
Bitcoin mining is becoming an increasingly energy-intensive process whose future implications for energy use and CO2 emissions remain poorly understood. This is in part because—like many IT systems—its computational efficiencies and service demands have been evolving rapidly. Therefore, scenario analyses that explore these implications can fill pressing knowledge gaps, but they must be approached with care. History has shown that poorly constructed scenarios of future IT energy use—often due to overly-simplistic extrapolations of early rapid growth trends—can do more harm than good by spreading misinformation and driving ill-informed decisions. Indeed, the utility of an energy demand scenario is directly proportional to its credibility, which is typically demonstrated through careful attention to technology characteristics and evolution, analytical rigor and transparency, and designing scenarios that align with plausible future outcomes.
Recently, connected vehicles (CV) are becoming a promising research area leading to the concept of CV as a Service (CVaaS). With the increase of connected vehicles and an exponential growth in the field of online cab booking services, new requirements such as secure, seamless and robust information exchange among vehicles of vehicular networks are emerging. In this context, the original concept of vehicular networks is being transformed into a new concept known as connected and autonomous vehicles. Autonomous vehicular use yields a better experience and helps in reducing congestion by allowing current information to be obtained by the vehicles instantly. However, malicious users in the internet of vehicles may mislead the whole communication where intruders may compromise smart devices with the purpose of executing a malicious ploy. In order to prevent these issues, a blockchain technique is considered the best technique that provides secrecy and protection to the control system in real time conditions. In this paper, the issue of security in smart sensors of connected vehicles that can be compromised by expert intruders is addressed by proposing a blockchain framework. This study has further identified and validated the proposed mechanism based on various security criteria, such as fake requests of the user, compromise of smart devices, probabilistic authentication scenarios and alteration in stored user's ratings. The results have been analyzed against some existing approach and validated with improved simulated results that offer 79% success rate over the above-mentioned issues.
International roaming is one of the many essential services a carrier enables on its customer's subscriber identity module (SIM) cards that allows its users to send and receive calls, messages, and e-mails whenever they travel to another country. From its beginnings in voice roaming in the last 1.5 decades up to today, international roaming has been a pivotal contributor to the sales of telecommunications carriers. It does however come at a high cost, which the users end up paying, due to numerous factors such as roaming agreements between home carriers and visited carriers as well as clearinghouses needed by companies to settle disputes in agreements between the carriers involved. This paper proposes a consortium blockchain approach coupled with smart contract application. The decentralized nature of a blockchain and the automation that smart contracts provide solves two of international roaming problems-intermediaries and high cost. Together with Tendermint-a consensus mechanism that requires no mining, implementation of the consortium blockchain can be done involving all carriers around the world with them being the privileged users and verify the transactions of two engaging carriers. With this setup, the blockchain is privatized yet still able to perform the essential functions of a blockchain, which are immutability, security, and transparency of data. The proposal can eliminate the need for continually changing roaming agreements and clearing houses that increase the price for the users as well as slow down the processing time making international roaming services much more efficient, user-friendly and cost-effective for both its consumers and carriers.
Ride-sharing is a service that enables drivers to share trips with other riders, contributing to appealing benefits of shared travel cost and reducing traffic congestion. However, the majority of existing ride-sharing services rely on a central third party to organize the service, which make them subject to a single point of failure and privacy disclosure concerns by both internal and external attackers. Moreover, they are vulnerable to distributed denial of service (DDoS) and Sybil attacks launched by malicious users and external attackers. Besides, high service fees are paid to the ride-sharing service provider. In this paper, we propose a decentralized ride-sharing service based on public Blockchain, named B-Ride. B-Ride enables drivers to offer ride-sharing services without relying on a trusted third party. Both riders and drivers can learn whether they can share rides while preserving their trip data, including pick-up/drop-off location, departure/arrival date and travel price. However, malicious users exploit the anonymity provided by the public blockchain to submit multiple ride requests or offers, while not committing to any of them, in order to find a better offer or to make the system unreliable. B-Ride solves this problem by introducing a time-locked deposit protocol for a ride-sharing by leveraging smart contract and zero-knowledge set membership proof. In a nutshell, both a driver and a rider have to show their good will and commitment by sending a deposit to the blockchain. Later, a driver has to prove to the blockchain on the agreed pick-up time that he/she arrived at the pick-up location on time. To preserve rider/driver privacy by hiding the exact pick-up location, the proof is performed using zero-knowledge set membership proof. Moreover, to ensure fair payment, a pay-as-you-drive methodology is introduced based on the elapsed distance of the driver and rider. In addition, we introduce a reputation model to rate drivers based on their past behaviour without involving any third-parties to allow riders to select them based on their history on the system. Finally, we implement our protocol and deploy it in a test net of Ethereum. The experimental results show the applicability of our protocol atop existing real-world blockchains.
Ride-sharing is a service that enables drivers to share their trips with\nother riders, contributing to appealing benefits of shared travel costs.\nHowever, the majority of existing platforms rely on a central third party,\nwhich make them subject to a single point of failure and privacy disclosure\nissues. Moreover, they are vulnerable to DDoS and Sybil attacks due to\nmalicious users involvement. Besides, high fees should be paid to the service\nprovider. In this paper, we propose a decentralized ride-sharing service based\non public Blockchain, named B-Ride. Both riders and drivers can find rides\nmatch while preserving their trip data, including pick-up/drop-off location,\nand departure/arrival date. However, under the anonymity of the public\nblockchain, a malicious user may submit multiple ride requests or offers, while\nnot committing to any of them, to discover better offer or to make the system\nunreliable. B-Ride solves this problem by introducing a time-locked deposit\nprotocol for a ride-sharing by leveraging smart contract and zero-knowledge set\nmembership proof. In a nutshell, both a driver and a rider have to show their\ncommitment by sending a deposit to the blockchain. Later, a driver has to prove\nto the blockchain on the agreed departure time that he has arrived at the\npick-up location. To preserve rider/driver location privacy by hiding the exact\npick-up location, the proof is done using zero-knowledge set membership\nprotocol. Moreover, to ensure a fair payment, a pay-as-you-drive methodology is\nintroduced based on the elapsed distance of the driver and the rider. Also, we\nintroduce a reputation-based trust model to rate drivers based on their past\ntrips to allow riders to select them based on their history on the system.\nFinally, we implement B-Ride in a test net of Ethereum. The experiment results\nshow the applicability of our protocol atop the existing real-world blockchain.\n
Siming Wang, Xumin Huang, Rong Yu, Yan Zhang · 5 authors
With the fast expanding scale of vehicular networks, vehicular edge computing (VEC) has emerged and attracted growing attention from both industry and academia. Parked vehicles (PVs) have great potential to join vehicular networks for sharing their idle computing and networking resources. However, due to the underlying security and privacy threats, it is challenging to fairly motivate PVs for resource sharing in an efficient and secure way. In this paper, we propose a permissioned vehicular blockchain for secure and efficient resource sharing in VEC, namely, Parkingchain. We first design smart contract to achieve secure resource sharing and efficient service provisioning between PVs and service requesters (SRs). A multi-weight subjective logic based delegated Byzantine Fault Tolerance (DBFT) consensus mechanism is presented to improve the consensus process in Parkingchain. Further, we design a contract theory-based incentive mechanism to model the interactions between SR and PVs under asymmetric information scenario. Finally, numerical results demonstrate that the proposed incentive mechanism is effective and efficient compared with existing schemes.
Roman Overko, Rodrigo Ordóñez-Hurtado, Sergiy Zhuk, Pietro Ferraro · 6 authors
We introduce a permissioned distributed ledger technology (DLT) design for crowdsourced smart mobility applications. This architecture is based on a directed acyclic graph architecture (similar to the IOTA tangle) and uses both Proof-of-Work and Proof-of-Position mechanisms to provide protection against spam attacks and malevolent actors. In addition to enabling individuals to retain ownership of their data and to monetize it, the architecture also is suitable for distributed privacy-preserving machine learning algorithms, is lightweight, and can be implemented in simple internet-of-things (IoT) devices. To demonstrate its efficacy, we apply this framework to reinforcement learning settings where a third party is interested in acquiring information from agents. In particular, one may be interested in sampling an unknown vehicular traffic flow in a city, using a DLT-type architecture and without perturbing the density, with the idea of realizing a set of virtual tokens as surrogates of real vehicles to explore geographical areas of interest. These tokens, whose authenticated position determines write access to the ledger, are thus used to emulate the probing actions of commanded (real) vehicles on a given planned route by "jumping" from a passing-by vehicle to another to complete the planned trajectory. Consequently, the environment stays unaffected (i.e., the autonomy of participating vehicles is not influenced by the algorithm), regardless of the number of emitted tokens. The design of such a DLT architecture is presented, and numerical results from large-scale simulations are provided to validate the proposed approach.
Zhenyu Zhou, Bingchen Wang, Mianxiong Dong, Kaoru Ota
Smart grid has emerged as a successful application of cyber-physical systems in the energy sector. Among numerous key technologies of the smart grid, vehicle-to-grid (V2G) provides a promising solution to reduce the level of demand-supply mismatch by leveraging the bidirectional energy-trading capabilities of electric vehicles. In this paper, we propose a secure and efficient V2G energy trading framework by exploring blockchain, contract theory, and edge computing. First, we develop a consortium blockchain-based secure energy trading mechanism for V2G. Then, we consider the information asymmetry scenario, and propose an efficient incentive mechanism based on contract theory. The social welfare optimization problem falls into the category of difference of convex programming and is solved by using the iterative convex-concave procedure algorithm. Next, edge computing has been incorporated to improve the successful probability of block creation. The computational resource allocation problem is modeled as a two-stage: 1) Stackelberg leader-follower game and 2) the optimal strategies are obtained by using the backward induction approach. Finally, the performance of the proposed framework is validated via numerical results and theoretical analysis.
In this paper, we develop a more general framework of block-structured Markov processes in the queueing study of blockchain systems, which can provide analysis both for the stationary performance measures and for the sojourn time of any transaction or block. In addition, an original aim of this paper is to generalize the two-stage batch-service queueing model studied in Li et al. (Blockchain queue theory. In: International conference on computational social networks. Springer: New York; 2018 . p. 25–40) both “from exponential to phase-type” service times and “from Poisson to MAP” transaction arrivals. Note that the MAP transaction arrivals and the two stages of PH service times make our blockchain queue more suitable to various practical conditions of blockchain systems with crucial factors, for example, the mining processes, the block generations, the blockchain building and so forth. For such a more general blockchain queueing model, we focus on two basic research aspects: (1) using the matrix-geometric solution, we first obtain a sufficient stable condition of the blockchain system. Then, we provide simple expressions for the average stationary number of transactions in the queueing waiting room and the average stationary number of transactions in the block. (2) However, on comparing with Li et al. ( 2018 ), analysis of the transaction–confirmation time becomes very difficult and challenging due to the complicated blockchain structure. To overcome the difficulties, we develop a computational technique of the first passage times by means of both the PH distributions of infinite sizes and the RG factorizations. Finally, we hope that the methodology and results given in this paper will open a new avenue to queueing analysis of more general blockchain systems in practice and can motivate a series of promising future research on development of blockchain technologies.
Increasingly, connected cars are becoming a decentralized data platform. With greater autonomy, they have growing needs for computation and perceiving the world around them through sensors. While todays generation of vehicles carry all the necessary sensor data and computation on board, we envision a future where vehicles can cooperate to increase their perception of the world beyond their immediate view, resulting in greater safety, coordination and more comfortable experience for their human occupants. In order for vehicles to obtain data, compute and other services from other vehicles or road side infrastructure, it is important to be able to make micro payments for those services and for the services to run seamlessly despite the challenges posed by mobility and ephemeral interactions with a dynamic set of neighboring devices. We present MOTIVE, a trusted and decentralized framework that allows vehicles to make peer to peer micropayments for data, compute and other services obtained from other vehicles or road side infrastructure within radio range. The framework utilizes distributed ledger technologies including smart contracts to enable autonomous operation and trusted interactions between vehicles and nearby entities.
In the Internet of Vehicles (IoV), data sharing among vehicles is critical for improving driving safety and enhancing vehicular services. To ensure security and traceability of data sharing, existing studies utilize efficient delegated proof-of-stake consensus scheme as hard security solutions to establish blockchain-enabled IoV (BIoV). However, as the miners are selected from miner candidates by stake-based voting, defending against voting collusion between the candidates and compromised high-stake vehicles becomes challenging. To address the challenge, in this paper, we propose a two-stage soft security enhancement solution: 1) miner selection and 2) block verification. In the first stage, we design a reputation-based voting scheme to ensure secure miner selection. This scheme evaluates candidates' reputation using both past interactions and recommended opinions from other vehicles. The candidates with high reputation are selected to be active miners and standby miners. In the second stage, to prevent internal collusion among active miners, a newly generated block is further verified and audited by standby miners. To incentivize the participation of the standby miners in block verification, we adopt the contract theory to model the interactions between active miners and standby miners, where block verification security and delay are taken into consideration. Numerical results based on a real-world dataset confirm the security and efficiency of our schemes for data sharing in BIoV.
The following article sums up the current problems of the logistics and explains how the Blockchain technology can help to solve some of them. A utility value analysis is used to quantify the scenarios the Blockchain is most likely to be used in. This offers a result that, in comparison to current research, does not only show the opportunities but also how likely they are to be used in these sections. In the next step these scenarios are compared with each other. These results lead to a outlook to potential applications of the Blockchain technology in the logistics.
Nghia Duong‐Trung, Xuan Son, Tan Tai, Phuong Ngoc Nam · 8 authors
To date, cash on delivery (COD) is one of the most popular payment methods in developing countries thanks to the blossom of customer-to-customer e-commerce. With the widespread of a very small business model and the Internet, online shopping has become part of people’s daily activity. People browse for desirable products at the comfort of their homes and ask the online vendor that a shipper can deliver the merchandise at their doorstep. Then, COD allows customers to pay in cash when the product is delivered to their desired location. Since customers receive goods before making a payment, COD is, therefore, considered as a payment system. However, the crucial issue that previous research has not yet addressed is that their models only support single delivering session at a time. More precisely, if the current buyer is not available to receive the goods, the shipper has to wastefully wait for the complete payment and he/she cannot start shipping another merchandise. The tracking system seems to poorly handle this issue. In particular, we propose a multi-session mechanism, which consists of blockchain technology, smart contracts and hyperledger fabric platform to achieve distributed and transparent across delivering sessions in the decentralized markets. Our proposed mechanism ensure the efficiency of delivering process. The authors release our sources codes for further reproducibility and development. We conclude that the integration of multi-session mechanism and blockchain technology will cause significant efficiency across several disciplines.
The issues in charging guiding for electric vehicles are meaningful studies in recent years, especially for electric taxis which need to be recharged during working hours. However, with the popularity of taxi-booking apps, how to obtain an effective charging guiding for taxis having advance orders becomes an urgent problem to be solved. To optimize various special interests while satisfying the constraints of online advance orders, a charging guiding strategy based on consortium blockchain is proposed in this paper. Firstly, a taxi charging guiding architecture based on consortium blockchain is designed, and an improved practical byzantine fault tolerance algorithm is proposed to solve the problem of charging information disconnection and trust between multiple charging station operators. Secondly, we establish the charging guiding model for electric taxis based on multi-objective optimization. The model aims to meet the constraints of online advance orders, maximize passengers' satisfaction and operators' service efficiency, and minimize the charging costs of taxis. Finally, the optimization model is solved by quantum-behaved particle swarm optimization. In order to verify the effectiveness of the proposed guiding strategy, main urban areas of a city are taken as examples for simulation. The results show that the proposed strategy has increased the passengers' satisfaction by 0.44%, and has decreased the expense cost, the time cost and distance cost by 2.38%, 5.72%, and 17.25% respectively, comparing with PSO based strategy while balancing the utilization of charging equipment.
The next generation of vehicles will be autonomous, connected, electric, and intelligent with distinct requirements such as high mobility, low latency, real-time applications, seamless connectivity, and security. Blockchain can provide a good solution to the issue of secure message dissemination or secure information sharing in vehicular networks with a weak trust relationship among the nodes. In this paper, we investigate the design of a regional blockchain for VANETs, where the blockchain is shared among nodes in a geographically bounded area. We investigate how to design the regional blockchain while achieving a low 51% attack success probability. We derive a condition that guarantees a low 51% attack success probability in terms of the numbers of good nodes and malicious nodes, the message delivery time, and the puzzle computation time. The condition can provide a useful guideline for selection of several control parameters guaranteeing the stable operation of the blockchain. We run several simulations to show the validity of the condition and investigate the effects of various parameters on the 51% attack success probability. Our analysis and simulation results show that maintaining a low message delivery time for good nodes is very important in protecting the stability of the blockchain system.
This paper investigates how mobility affects the performance of a blockchain system operating in a vehicular ad hoc network (VANET). The mobility of nodes incurs a unique challenge to a blockchain system due to continuous change and dynamicity in the connectivity of the nodes. Specifically, the mobility makes a proof-of-work (PoW) process difficult since while moving the nodes can only have a limited length of time for a “rendezvous” to exchange a new block for verification. For this reason, accurate modeling for the block exchange behavior in a VANET is also challenging, which nevertheless has not been discussed in previous studies. Therefore, this paper provides an analysis framework that formulates the impact of mobility on a blockchain system's performance in a VANET based on three key metrics: (i) the probability of a successful addition of block to the chain; (ii) the stability of a rendezvous, and; (iii) the number of blocks exchanged during a rendezvous. The closed-form expressions and numerical results display the performance of a blockchain system in various scenarios in a VANET.
This paper presents an efficient solution for the booking and payments functionality of a car sharing system that allows individuals to share their personal, underused cars in a completely decentralized manner, annulling the need of an intermediary. Our solution, named SC2Share, leverages smart contracts and uses them to carry out secure and private car booking and payments. Our experiments on SC2Share on the Ethereum testnet guarantee high security and privacy to its users and confirm that our system is cost-efficient and ready for practical use.
Haiqing Liu, Yan Zhang, Shiqiang Zheng, Yuancheng Li
In order to realize peer-to-peer (P2P) transactions between electric vehicles (EVs) in vehicle-to-grid (V2G) networks, we propose an EV power trading model based on blockchain and smart contract. Firstly, based on the blockchain and smart contract technology, a decentralized power trading model is proposed to realize the information equivalence and transparent openness of power trading. Then, considering the randomness and uncertainty of EV charging and discharging, the EV trading parties use the reverse auction mechanism based on dynamic pricing strategy to complete the transaction matching, which can not only improve the profit of the less competitive power seller, but also it can reduce the cost of the electricity purchaser. Finally, in order to verify the feasibility of our proposed scheme, V2G's EV power trading smart contract was designed, and the smart contract was released to Ethereum and simulated experiments were carried out. The effectiveness of the proposed scheme is verified by simulation experiments and comparison with traditional power trading schemes.
Jan 1, 2019·Proceedings of the ... Annual Hawaii International Conference on System Sciences/Proceedings of the Annual Hawaii International Conference on System Sciences
Alexander Schoenhals, Thomas Hepp, Stephan Leible, Philip Ehret · 5 authors
The licensing of creative work is of broad and current interest. The European Commission proposes that when uploading a licensed digital work, the uploader should be checked by the system that one has the necessary rights. Technically this law is difficult to implement, as images with different intentions are shared, and even small changes like watermarks make it difficult to reveal similarities. The characteristics of distributed ledger technology could provide excellent support for the licensing and management of the rights of use. In this work, non-technical and technical criteria are defined to achieve an overview of the state-of-the-art solutions in the field of blockchain-based licensing platforms. Based on the criteria, different licensing platforms are reviewed, and the results are presented in a comparison matrix.