Privacy-enhancing distributed protocol for data aggregation based on blockchain and homomorphic encryption

The recent increase in reported incidents of security breaches compromising users' privacy call into question the current centralized model in which third-parties collect and control massive amounts of personal data. Blockchain has demonstrated that trusted and auditable computing is possible using a decentralized network of peers accompanied by a public ledger. Furthermore, Homomorphic Encryption (HE) guarantees confidentiality not only on the computation but also on the transmission, and storage processes. The synergy between Blockchain and HE is rapidly increasing in the computing environment. This research proposes a privacy-enhancing distributed and secure protocol for data aggregation backboned by Blockchain and HE technologies. Blockchain acts as a distributed ledger which facilitates efficient data aggregation through a Smart Contract. On the top, HE will be used for data encryption allowing private aggregation operations. The theoretical description, potential applications, a suggested implementation and a performance analysis are presented to validate the proposed solution.This work has been partially supported by the Basque Country Government under the ELKARTEK program, project TRUSTIND (KK- 2020/00054). It has also been partially supported by the H2020 TERMINET project (GA 957406)

The development of distributed and peer-to-peer systems for future smart grids

The widespread application of smart grid concept has promoted the development of modern power systems featured with smart facilities, distributed resources and advanced ICT, and shifted towards complex cyber-physical and internet-of-things (IoT) embedded system. The traditional centralized system structure or management mode is faced with the challenges of coping with the growing network traffic, computing burden, demand for flexible services, and risks from cyber-attacks. In this regard, the development of distributed systems, as a valuable research theme, has sparked attentions from researchers and practitioners, which involves several crucial concerns including data security, reliability, and privacy. As a potential solution, blockchain (BC) technology shows its proper applicability due to its characteristics, but it encounters some problems such as unsatisfied resource efficiency. Meanwhile, the increasing integration of distributed system and distributed renewable generation in power system has raised challenges in the system stability and efficient management. In above context, this research focuses on the development of distributed and peer-to-peer (P2P) systems for future smart grids. Firstly, the research comprehensively reviews the-state-of-art of BC and IoT in smart grids, then put forwards their potential application scenarios in future grids with discussing the related challenges. Afterwards, this research integrates homomorphic cryptography with the technical components of BC as a basic paradigm to propose a distributed, secure and privacy-preserving smart meter data aggregation framework, providing the utility with high robust data management services. In addition, an agent bidding based trading scheme is designed for users to purchase electricity from the small-scale renewable power plant under stand-alone system, making individual bidding data not exposed in the storage and entire trading process even if the distributed system nodes are eavesdropped. In order to cope with the negative influences from distributed generation, this research proposes a deviation penalty method to help narrow the gap between the real-time demand/output and pre-determined transaction outcomes in P2P trading under power distribution system. At the end of this thesis, the potential future research works are discussed

Distributed meter data aggregation framework based on Blockchain and homomorphic encryption

A significant progress in modern power grids is witnessed by the tendency of becoming complex cyber-physical systems. As a fundamental physical infrastructure, smart meter in the demand side provides real-time energy consumption information to the utility. However, ensuring information security and privacy in the meter data aggregation process is a non-trivial task. This study proposes a distributed, privacy-preserving, and secure meter data aggregation framework, backed up by Blockchain and homomorphic encryption (HE) technologies. Meter data are aggregated and verified by a hierarchical Blockchain system, in which the consensus mechanism is supported by the practical Byzantine fault tolerance algorithm. On the top of the Blockchain system, HE technology is used to protect the privacy of individual meter data items during the aggregation process. Performance analysis is conducted to validate the proposed method