Aug 1, 2019·2019 18th IEEE International Conference On Trust, Security And Privacy In Computing And Communications/13th IEEE International Conference On Big Data Science And Engineering (TrustCom/BigDataSE)
Alexander Marsalek, Thomas Zefferer, Edona Fasllija, Dominik Ziegler
In blockchain-based solutions, the amount of data stored in the blockchain increases steadily. Considerable amounts of data accordingly need to be download and stored at decentralized nodes to carry out meaningful validations. For the Bitcoin blockchain, approximately 197 GB must currently be downloaded and processed by any node aiming to fully verify the correctness of stored transactions. This represents an emerging problem with respect to resource-constrained thin clients that lack the required download or storage capacities, but with which meaningful validations still need to be carried out. This problem will gain even more relevance in the future, as blockchain technology is applied to new domains such as the Internet of Things (IoT) that necessitate the use of thin clients. We address this emerging problem by proposing a novel compressible blockchain architecture. In our proposal, we use a snapshot-based approach, to create snapshots of the blockchain at regular intervals and store them in blocks. These blocks are chained, forming a second blockchain that is linked to the primary chain. In this way, the amount of data that needs to be downloaded and stored by decentralized nodes is reduced considerably, while the full validation of the entire blockchain still remains feasible. In this paper, we describe the proposed compressible blockchain architecture in detail. We conducted evaluations that demonstrate the feasibility of the proposed solution and show its advantages over related approaches introduced in the literature. Overall, our design can be used to reduce the size of the blockchain by up to 93%, facilitating secure blockchain-based applications even on resource-constrained thin clients such as IoT devices.
By outsourcing most of storage and computational tasks to full nodes, Ethereum lightweight client is able to run on the resource-limited devices such as mobile phones. In the interactions with the lightweight client, the full node obtains considerable information about Ethereum addresses (Ethereum accounts), transactions, and transaction receipts associated with the lightweight client. This behavior obviously violates user privacy. Currently, there is no solution supporting the lightweight client to efficiently retrieve the account state, related transactions, and transaction receipts from the untrust full node without revealing privacy. In this paper, we propose to use private information retrieval (PIR) to design a privacy-preserving Ethereum lightweight client. Since directly using existing PIR scheme significantly increases communication overhead of the lightweight client, we tailor existing PIR schemes to adapt to the lightweight client, which allows the lightweight client to efficiently retrieve account state and transaction data without leaking sensitive query information. Security and performance analysis show that our scheme is capable of efficiently and privately downloading the data of interest to the lightweight client.
Shivam Saxena, Hany E. Z. Farag, Aidan Brookson, Hjalmar Turesson · 5 authors
This paper proposes a peer to peer (P2P), blockchain based energy trading market platform for residential communities with the objective of reducing overall community peak demand and household electricity bills. Smart homes within the community place energy bids for its available distributed energy resources (DERs) for each discrete trading period during a day, and a double auction mechanism is used to clear the market and compute the market clearing price (MCP). The marketplace is implemented on a permissioned blockchain infrastructure, where bids are stored to the immutable ledger and smart contracts are used to implement the MCP calculation and award service contracts to all winning bids. Utilizing the blockchain obviates the need for a trusted, centralized auctioneer, and eliminates vulnerability to a single point of failure. Simulation results show that the platform enables a community peak demand reduction of 46%, as well as a weekly savings of 6%. The platform is also tested at a real-world Canadian microgrid using the Hyperledger Fabric blockchain framework, to show the end to end connectivity of smart home DERs to the platform.
Research and apply blockchain technologies for e-commerce, finance and energy. The blockchain system includes blockchain technology components, blockchain application programming interfaces, and applications. The blockchain-based applications cover supply chain finance, e-commerce transactions, product traceability, user credits, financial services, trust systems, new energy, etc. Based on blockchain technology, it builds a creative and security trading system, payment system and trust system for e-commerce, financial services and new energy business.
As a decentralized ledger technology, blockchain is considered to be a potential solution for applications with highly concentrated management mechanism. However, most of the existing blockchain networks are employed with the hash-puzzle-solving consensus protocol, known as proof-of-work. The competition of solving the puzzle introduces high latency, which directly leads to a long transaction-processing time. One solution of this dilemma is to establish a blockchain network with shards. In this paper, we focus on the blockchain network with shards and adopt the security-deposit based consensus protocol, studying the problem of how to balance the security incentive and the economic incentive. Also, the inherent features of the blockchain, i.e., anonymity and decentralization, introduce the information asymmetric issue between the beacon chain and the participants. The contract theory is utilized to formulate the problem between them. As such, the optimal rewards related to the different types of validators can be obtained, as well as the reasonable deposits accordingly. Compared with the fixed deposits, the flexible deposits can provide enough economic incentive for the participants without losing the security incentives. Besides, the simulation results demonstrate that the contract theory approach is capable of maximizing the beacon chain's utility and satisfying the incentive compatibility and individual rationality of the participants.
Due to its immutable and transparent nature, Blockchain (BC) provided a decentralized solution to overcome security and resource challenges of centralized Internet of Things (IoT). However, its integration with IoT is limited by scalability and expensive computation. To this end, we propose a two-layer-consensus based BC architecture optimized for IoT requirements. Low resource devices attached to the server and with users and other nodes form Base-Layer. There is a high-scalable and fully decentralized blockchain performing basic functions maintaining in Base-Layer, myriad blocks are mined and submitted every round, but only one block selected by Top-Layer can be recorded. Top-Layer with another high-security blockchain is formed by special nodes running a Non-byzantine fault tolerance algorithm to determine the accounting rights in random. Analysis and evaluation show that consensus has better fault tolerance and increases scalability.
Farhan Ahmad, Chaker Abdelaziz Kerrache, Fatih Kurugöllü, Rasheed Hussain
The revolution of Internet-of-vehicles (IoV) has stimulated a substantial response from academia, research, and industry due to its massive potential to improve overall transportation. Current IoV faces huge challenges due to its reliance on IP-based network architecture. Therefore, named data networking (NDN) is proposed as a promising architecture to solve issues posed by IP-based systems. Recently, blockchains (BCs) have been utilized within IoV to increase network security. However, the integration of BC within NDN-enabled IoV is still an open research problem. In this study, we proposed a novel tier-based architecture known as “Blockchain in NDN-enabled Internet-of-vehicles (BINDN),” which can support BC within NDN-enabled IoV. BINDN can be used as reference architecture to design security solutions in NDN-enabled IoV using BC. Furthermore, it provides an extensive set of applications including IoV security, trust management, and privacy enhancements. Moreover, we highlighted major challenges and issues when integrating BC within NDN-enabled IoV.
Blockchains can now be used to distribute digital assets independent of specific organizations. One way to handle digital assets on a blockchain is through tokens. Tokens define chunks of data on a blockchain, allowing it to be distributed like virtual currency. However, storing all data related to digital assets in a token is difficult. Data is currently managed separately because storing a large amount of data in a blockchain can cause the ledger to grow large. When the management of data depends on a particular organization, the stability of the token's value depends on that particular organization. In this paper, we propose an organization-independent management method that combines a distributed content-addressable file system with a blockchain. Our proposed method places the data associated with the token and the access information to the token into the distributed content-addressable file system. As a result, the token associated with the data has the sharing control of the data stored in the distributed content-addressable file system, and a configuration independent of the specific contract is realized.
In this paper, the performance evaluation for Internet of Things based on blockchain Technology is proposed. In a blockchain network, all IoT devices communicate and synchronize with each other and allow device to transact with each other directly without the need of trusted intermediary. IoT devices have a smart contract associate with them which are deployed on the blockchain network. User or device who wish to use a service can transact to smart contract that associated with IoT device. Moreover, all transactions of IoT device, device-to device or human-to-device, will not only permanently store on Blockchain network but also gain the security and privacy of them. In this implementation, a private Ethereum network is chosen to use as a blockchain platform and the raspberry pi act as a lightweight node to transact with a smart contract in a full node which install on PC desktop. In addition, the performance evaluation of two realistic traffic flow, store and access transactions, such as latency, execution time and throughput are highlight.
Internet of Things (IoT) plays an indispensable role in our daily life, in many cases, IoT systems are implemented following the client-server paradigm, which are vulnerable to single point of failures and malicious attacks. Due to the resilience and security promise of blockchain, the idea of combining blockchain and IoT has gained considerable attention in recent years. However, blockchains are power-intensive and low-throughput, which may not suitable for power-constrained IoT devices. To tackle these challenges, we present B-IoT, a blockchain based IoT system with credit-based consensus mechanism. We propose a credit-based proof-of-work (PoW) mechanism for IoT devices, which enhances security and improves transaction efficiency simultaneously. In order to protect the confidentiality of sensitive IoT data, we design a data authority management method to regulate the access to sensor data. In addition, our system is built based on a directed acyclic graph (DAG)-structured blockchain, which is more efficient than the satoshi-style blockchain. We implement a prototype of B-IoT on Raspberry Pi, and conduct case studies of a smart factory. Extensive evaluation and analysis results demonstrate that the proposed credit-based PoW mechanism and data access control are practical for IoT.
Private and consortium blockchains have recently raised interest in the blockchain community around facilitating business collaboration. In a business network, multiple participants either (1) work with a centralized authority to maintain a complete and verifiable ledger, or (2) transact in a decentralized manner to maintain an independent shared ledger. A centralized, private blockchain system, such as Amazon QLDB, addresses scenario one with good price-to-performance ratio. The second scenario is commonly backed by a consortium blockchain network, such as Hyperledger Fabric, that requires greater and more complex hardware and software to handle complicated consensus and peer-to-peer communications. The disparate design objectives and resultant principles complicate efforts to handle both scenarios within a single blockchain system. Moreover, the two situations are often mixed together for a user in different business activities, and interchangeable with the evolution of the business collaboration. From the outset, users face a dilemma in choosing which blockchain system type will handle their long-term needs. In this paper, we present a novel Full-Spectrum Blockchain as a Service (FSBaaS) built on top of a high-performance centralized private blockchain runtime called Blockchain Lite and a Hyperledger Fabric blockchain runtime. It handles different scenarios flexibly by providing a unified interface for the two blockchain runtimes from programing model and RESTful APIs to the tenant model. A BaaS tenant can subscribe to the two runtimes simultaneously and migrate data from one to the other as needed. Experimental results contrasted the performance of two blockchain runtimes and the practicality of the proposed BaaS.
Blockchain is seen as a promising technology to provide reliable and secure services due to its decentralized characteristic. However, because of the limited throughput, current blockchain platforms can not meet the transaction demand in practical use. Though researchers proposed many new solutions, they suffered either decentralization or security issues. In this paper, using Directed Acyclic Graph (DAG) structure, we improve the linear structure of traditional blockchain protocol. In the new structure, blocks are organized in levels and width, which will generate into a compacted DAG structure (CoDAG). To make CoDAG more efficient and secure, we design algorithms and protocols to place the new-generated blocks appropriately. Compared with traditional blockchain protocols, CoDAG improves the security and transaction verification time, and enjoys the consistency and liveness properties of blockchain. Taking adversary parties into consideration, two possible attack strategies are presented in this paper, and we further prove that CoDAG is a secure and robust protocol to resist them. The experimental results show that CoDAG can achieve 394 transactions per second, which is 56 times of Bitcoin's throughput and 26 times of Ethereum's.
Anas Dawod, Dimitrios Georgakopoulos, Prem Prakash Jayaraman, Ampalavanapillai Nirmalathas
This position paper presents recent results in developing a blockchain-based solution for Global IoT Device Discovery and Integration (GIDDI). GIDDI makes IoT application development more efficient and cost-effective via enabling (1) sharing and reuse of existing IoT devices owned and maintained by different providers, and (2) deployment of new IoT devices that is supported by a revenue generation scheme for their providers. More specifically, this paper proposes a distributed IoT ledger that is specifically designed for managing the metadata needed for GIDDI. This GIDDI Blockchain is IoT-owned (i.e., it is not controlled by any individual or organization) and is IoT-scaled (i.e., it can support the discovery and reuse of millions of IoT devices). In addition to the GIDDI Blockchain, this paper outlines the design of a GIDDI Marketplace that provides the functionality needed for IoT device registration, query, integration, payment and security via the proposed GIDDI Blockchain. Finally, the paper outlines a prototype GIDDI Blockchain implementation and discusses future research in this area.
Blockchain is receiving huge attention from researchers and various organizations as it brings forth magical solutions to the classical centralized architecture problems. Blockchain, either private or public, is a kind of distributed ledger for maintenance of integrity among various transactions by the process of ledger decentralization among the participating end users. On the contrary, Internet of Things (IoT) is the internet revolution that facilitates connection of all end user devices over the internet so that they can share their services and applications for improvement of daily living standards. Centralized IoT provides numerous benefits, however, it also brings forth several security challenges. Integrating blockchain with IoT is an effective way to resolve these security challenges. This paper presents a detailed review that highlights this integration process. The paper presents the working mechanism of the blockchain and how it changes the nature of value. Application areas and security challenges are also outlined and discussed in the paper.
Ride sharing is a centralized trust based system where users trust the service providers for the ride set up, tracking, cancellation, fare calculation etc. Any malicious activity in the centralized server based system or driver or rider destroys the fairness involved in the ride and causes inconvenience to the parties. After the completion of the ride, the drivers are rated by the riders. There are possibilities that, a malicious rider can claim the refund with a fake complain and give the driver poor rating. Current system is not capable of deciding the correctness of the objections raised by either parties and provides a biased outcome of each objections as per the centralized company's marketing strategies. We present BlockV, a blockchain enabled solution to ensure the fairness of the ride. The creation, completion, dissatisfaction or abortion of any ride will be written in the blockchain ledger, hence will be available to all participants in the peer to peer network. This simultaneously ensures the fairness in maintenance of the inbuilt reputation system. We have implemented a prototype in Ethereum private network and KOVAN test network and the analysis is included.
Jul 1, 2019·2019 International Conference on Internet of Things (iThings) and IEEE Green Computing and Communications (GreenCom) and IEEE Cyber, Physical and Social Computing (CPSCom) and IEEE Smart Data (SmartData)
Abdur R. Shahid, Niki Pissinou, Corey Staier, Rain Kwan
The Internet of Things (IoT), forming the foundation of Cyber Physical Systems (CPS), connects a huge number of ubiquitous sensing and mobile computing devices. The mobile IoT systems generate an enormous volume of a variety of dynamic context data and typically count on centralized architectures to process them. However, their inability to ensure security and decline in communication efficiency and response time with the increase in the size of IoT network are some of the many concerning weaknesses that are holding back the fast-paced growth of IoT. Realizing the limitations of centralized systems, recently blockchain-based decentralized architecture is being considered as the key to redesigning the IoT systems in a way that is designed to be secure, transparent, highly resistant to outages, auditable, and efficient. However, before realizing the new promise of blockchain for IoT, there are significant challenges to address. One fundamental challenge is the scale issue around data collection, storage, and analytic as IoT sensor devices possess limited computational power and storage capabilities. In particular, since the chain is always growing, IoT devices require more and more resources. Thus, an oversized chain poses storage and scalability problems. With this in mind, the overall goal of our research is to design a lightweight scalable blockchain framework for IoT of mobile devices. This framework, coined as "Sensor-Chain", promises a new generation of lightweight blockchain management with a superior reduction in resource consumption, and at the same time capable of retaining critical information about the IoT systems of mobile devices.
Blockchain is an immutable, transparent, public ledger that is distributed among the nodes in the network. It is a decentralized system in which transactions run on untrusted devices. To ensure equality and fairness, these transactions need to agree on some protocols. They are known as consensus algorithms. They are the core of blockchain and decide how blockchain works. Applying these algorithms, it is almost impossible for unauthorized users to crack the confidential information in the blocks. However, there are some security and performance issues that are required to be improved. In this paper, we have an overlook on various consensus algorithms, their working and where they are applied. In addition, we have reviewed blockchain technology, its application areas, advantages, and issues.
While Bitcoin dominates the market for cryptocurrencies, its use in micropayments is still a challenge due to its long transaction validation times and high fees. Recently, the concept of off-chain payments is introduced that led to the idea of establishing a payment network called Lightning Network (LN). Off-chain links provide the ability to do transactions without writing to Blockchain. However, LN's design still favors fees and is creating hub nodes that defeat the purpose of Blockchain. In addition, it is still not reliable as not all the transactions are guaranteed to be transmitted to their destinations. If current retailers would like to use it, these problems might hinder its adoption. To address this issue, in this paper, we advocate creating a private payment network among a given set of retailers that will serve their business needs, just like the idea of private Blockchains. The goal is to build a pure peer-to-peer topology that will eliminate the need for relays and increase the robustness of payments. Using off-chain links as edges and retailers as nodes, the problem is formulated as a multi-flow commodity problem where transactions represent the commodities from various sources to destinations. As the multi-flow commodity problem is NP-Complete, we propose a heuristic approach that utilizes Dijkstra's shortest path algorithm in a dynamic way by updating the edge weights when new payment paths are to be found. The order of transactions is randomized to provide fairness among the retailers. The evaluations indicate that the proposed heuristic comes close to an optimal solution while providing scalability and user privacy.
The fast developing Industrial Internet of Things (IIoT) technologies provide a promising opportunity to build large-scale systems to connect numerous heterogeneous devices into the Internet. Most existing IIoT infrastructures are based on a centralized architecture, which is easier for management but cannot effectively support immutable and verifiable services among multiple parties. Blockchain technology provides many desired features for large-scale IIoT infrastructures, such as decentralization, trustworthiness, trackability, and immutability. This paper presents a blockchain-based IIoT architecture to support immutable and verifiable services. However, when applying blockchain technology to the IIoT infrastructure, the required storage space posts a grant challenge to resource-constrained IIoT infrastructures. To address the storage issue, this paper proposes a hierarchical blockchain storage structure, \textit{ChainSplitter}. Specially, the proposed architecture features a hierarchical storage structure where the majority of the blockchain is stored in the clouds, while the most recent blocks are stored in the overlay network of the individual IIoT networks. The proposed architecture seamlessly binds local IIoT networks, the blockchain overlay network, and the cloud infrastructure together through two connectors, the \textit{blockchain connector} and the \textit{cloud connector}, to construct the hierarchical blockchain storage. The blockchain connector in the overlay network builds blocks in blockchain from data generated in IIoT networks, and the cloud connector resolves the blockchain synchronization issues between the overlay network and the clouds. We also provide a case study to show the efficiency of the proposed hierarchical blockchain storage in a practical Industrial IoT case.