Andreas Sendros

Aging urban water distribution networks face increasing pressure from growing demand and infrastructure deterioration, while the integration of IoT monitoring systems highlight the urgent need for innovative and sustainable solutions that enhance system reliability and ensure data security. At the same time, the fragmented nature of water governance creates further barriers to coordinated, transparent, and efficient water management. Our work aims to address these challenges by proposing a holistic architecture for a customized private permissioned blockchain network specifically designed for IoT-enabled water meters. This approach mitigates data breaches, ensures secure data sharing among IoT devices, and facilitates precise water usage measurements and real-time leak detection.To address these water management challenges, we developed an automated framework for the deployment, management, and updating of Hyperledger Fabric blockchains networks, specifically tailored for public utility services. The network leverages chaincodes to secure IoT data storage and analysis, effectively preventing unauthorized access and malicious actions. Furthermore, Ricardian Contracts are employed to ensure that decision-making processes align with the legal agreements between consumers and service providers, guaranteeing automatic regulatory compliance.The project’s architecture supports hierarchical data access, ensuring confidentiality and privacy across water management agencies, regulatory agencies, and data owners. A proof of concept has been successfully implemented across two Greek municipalities, involving five organizations and over 150 water meters.

The cost of interacting with a blockchain and the time required to search and retrieve information from it are important factors in the design of Decentralized Applications (DApps). The corresponding approaches for data management in Ethereum vary from pure on-chain solutions to hybrid architectures. In this work, we thoroughly examine a wide range of data management methods, including unconventional ones, and evaluate them in terms of storage cost and retrieval latency while considering the impact of recent hard forks. More precisely, we elaborate on the use of Smart Contract (SC) storage as a data store for DApps and in view of the prohibitive cost inherent to this approach, we present and compare methods for low-cost data handling in Ethereum, namely the event-logs, the transaction payload, and the almost surprising exploitation of unused function arguments. In addition, we study hybrid schemes by using IPFS and Swarm as storage platforms and Ethereum as a timestamping proof mechanism. Such schemes are especially effective when large chunks of data have to be managed. The upload and retrieval performance of these platforms and the cost associated with storing (on-chain) the identifiers of the uploaded data are of utmost importance and therefore are investigated in detail.

Blockchain is a distributed, immutable ledger technology initially developed to secure cryptocurrency transactions. Following its revolutionary use in cryptocurrencies, blockchain solutions are now being proposed to address various problems in different domains, and it is currently one of the most “disruptive” technologies. This paper presents a scoping review of the scientific literature for exploring the current research area of blockchain applications in the agricultural sector. The aim is to identify the service areas of agriculture where blockchain is used, the blockchain technology used, the data stored in it, its combination with external databases, the reason it is used, and the variety of agricultural products, as well as the level of maturity of the respective approaches. The study follows the PRISMA-ScR methodology. The purpose of conducting these scoping reviews is to identify the evidence in this field and clarify the key concepts. The literature search was conducted in April 2021 using Scopus and Google Scholar, and a systematic selection process identified 104 research articles for detailed study. Our findings show that in the field, although still in the early stages, with the majority of the studies in the design phase, several experiments have been conducted, so a significant percentage of the work is in the implementation or piloting phase. Finally, our research shows that the use of blockchain in this domain mainly concerns the integrity of agricultural production records, the monitoring of production steps, and the monitoring of products. However, other varied and remarkable blockchain applications include incentive mechanisms, a circular economy, data privacy, product certification, and reputation systems. This study is the first scoping review in this area, following a formal systematic literature review methodology and answering research questions that have not yet been addressed.