Now showing 1 - 3 of 3
  • Publication
    A Delay-Tolerant Payment Scheme Based on the Ethereum Blockchain
    Digital banking as an essential service can be hard to access in remote, rural regions where the network connectivity is unavailable or intermittent. The payment operators like Visa and Mastercard often face difficulties reaching these remote, rural areas. Although micro-banking has been made possible by short message service or unstructured supplementary service data messages in some places, their security flaws and session-based nature prevent them from wider adoption. Global-level cryptocurrencies enable low-cost, secure, and pervasive money transferring among distributed peers, but are still limited in their ability to reach people in remote communities. We propose a blockchain-based digital payment scheme that can deliver reliable services on top of unreliable networks in remote regions. We focus on a scenario where a community-run base station provides reliable local network connectivity while intermittently connects to the broader Internet. We take advantage of the distributed verification guarantees of the Blockchain technology for financial transaction verification and leverage smart contracts for secure service management. In the proposed system, payment operators deploy multiple proxy nodes that are intermittently connected to the remote communities where the local blockchain networks, such as Ethereum are composed of miners, vendors, and regular users. Through probabilistic modeling, we devise design parameters for the blockchain network to realize robust operation over the top of the unreliable network. Furthermore, we show that the transaction processing time will not be significantly impacted due to the network unreliability through extensive emulations on a private Ethereum network. Finally, we demonstrate the practical feasibility of the proposed system by developing Near Field Communication (NFC)-enabled payment gateways on Raspberry-Pis, a mobile wallet application and mining nodes on off-The-shelf computers.
      306Scopus© Citations 66
  • Publication
    Blockchain based Proxy Re-Encryption Scheme for Secure IoT Data Sharing
    Data is central to the Internet of Things IoT ecosystem. Most of the current IoT systems are using centralized cloud-based data sharing systems. Involvement of such third-party service provider requires also trust from both sensor owner and sensor data user. Moreover, the fees need to be paid for their services. To tackle both the scalability and trust issues and to automatize the payments, this paper presents a blockchain based proxy re-encryption scheme. The system stores the IoT data in a distributed cloud after encryption. To share the collected IoT data, the system establishes runtime dynamic smart contracts between the sensor and the data user without the involvement of a trusted third party. It also uses an efficient proxy re-encryption scheme which allows that the data is only visible by the owner and the person present in the smart contract. The proposed system is implemented in an Ethereum based testbed to analyze the performance and security properties.
    Scopus© Citations 88  703
  • Publication
    Proxy re-encryption enabled secure and anonymous IoT data sharing platform based on blockchain
    Data is central to the Internet of Things (IoT) ecosystem. With billions of devices connected, most of the current IoT systems are using centralized cloud-based data sharing systems, which will be difficult to scale up to meet the demands of future IoT systems. The involvement of such a third-party service provider requires also trust from both the sensor owner and sensor data user. Moreover, fees need to be paid for their services. To tackle both the scalability and trust issues and to automatize the payments, this paper presents a blockchain-based marketplace for sharing of the IoT data. We also use a proxy re-encryption scheme for transferring the data securely and anonymously, from data producer to the consumer. The system stores the IoT data in cloud storage after encryption. To share the collected IoT data, the system establishes runtime dynamic smart contracts between the sensor and data consumer without the involvement of a trusted third-party. It also uses a very efficient proxy re-encryption scheme which allows that the data is only visible by the owner and the person present in the smart contract. This novel combination of smart contracts with proxy re-encryption provides an efficient, fast and secure platform for storing, trading and managing sensor data. The proposed system is implemented using off-the-shelf IoT sensors and computer devices. We also analyze the performance of our hybrid system by using the permission-less Ethereum blockchain and compare it to the IBM Hyperledger Fabric, a permissioned blockchain.
    Scopus© Citations 71  367