Key characteristics to create optimized blockchain consensus algorithms

Blockchain is a fairly new technology and still in its infancy. As a result, many research papers are creating optimized consensus algorithms. Therefore, a need for key characteristics to create optimized blockchain consensus algorithms has been identified. This research paper presents the results of a systematic literature on identifying the main blockchain consensus algorithms and their associated advantages and disadvantages. Papers from four different databases were retrieved and after exclusion criteria were applied, 44 papers were ultimately included in the review. Results indicated that the five main consensus algorithms were Proof-of-Work (PoW), Proof-of-Stake (PoS), Practical Byzantine Fault Tolerance (PBFT), and Delegated Proof-of-Stake. The results further indicated that efficiency was the main advantage of the PoS, PBFT, PoA and hybrid consensus algorithms. The main disadvantage was “energy wastage” and was attributed to the PoW algorithm. Security concerns were the main disadvantage of the PoS algorithm. These findings were used to present key characteristics that future researchers can have in mind when creating optimized blockchain consensus algorithms.https://www.springer.com/series/558hj2022Informatic

Blockchain-based solution for energy demand-side management of residential buildings

Abstract Smart homes, connected through a network, can optimize the energy consumption and general load shape of their area. In this work, a blockchain-based smart solution is presented for demand-side management of residential buildings in a neighborhood to improve Peaks to Average Ratios (PAR) of power load, reduce energy consumption, and increase the thermal comfort of occupants by modeling heating, illumination, and appliance systems. For real-time power and temperature monitoring of the neighborhood, a transient numerical physical model has been developed. The simulator has been validated with data measured from a building in Northern Italy. Then, a neighborhood with 2,000 households has been modeled for different occupancy patterns, initial values, and boundary conditions. Two different control scenarios, namely basic and smart, have been considered. In the basic scenario, everything is managed by occupants except the boiler, which is controlled by the indoor temperature of the home. Instead, in the smart scenario, a blockchain-based network has been introduced for buildings to exchange a parameter called the Probability of the Next Hour (PNH). Ethereum Solidity has been deployed for smart contract development in the blockchain. The results show that using blockchain-connected smart controllers aimed at demand-side management can improve PAR, comfort level, and energy efficiency of buildings, which can bring about CO2 reduction on an urban and even global scale

Proof-of-Authentication for Scalable Blockchain in Resource-Constrained Distributed Systems

© 2019 IEEE. Resource -constrained distributed systems such as the Internet of Things (IoT), edge computing and fog computing are deployed for real-time monitoring and evaluation. Current security solutions are problematic when there is a centralized controlling entity. The blockchain provides decentralized security architectures using proof-of-work (PoW). Proof-of-work is an expensive process for IoT and edge computing due to the deployment of resource-constrained devices. This paper presents a novel consensus algorithm called Proof-of-Authentication (PoAh) to replace Proof-of-Work and introduce authentication in such environments to make the blockchain application-specific. This paper implemented the Proof-of-Authentication system to evaluate its sustainability and applicability for the IoT and edge computing. The evaluation process is conducted in both simulation and real-time testbeds to evaluate performance. Finally, the process of Proof-of-Authentication and its integration with blockchain in resource-constrained distributed systems is discussed. Our proposed PoAh, while running in limited computer resources (e.g. single-board computing devices like the Raspberry Pi) has a latency in the order of 3 secs

Optimising the sustainability of blockchain-based systems: balancing environmental sustainability, decentralisation and trustworthiness

Blockchain technology is an emerging technology revolutionising information technology and represents a change in how information is shared. It has captured the interest of several disciplines because it promises to provide security, anonymity and data integrity without any third-party control. Although blockchain technology has great potential for the construction of the future of the digital world, it is facing a number of technical challenges. A most critical concern is related to its environmental sustainability. It has been acknowledged that blockchain-based systems' energy consumption and carbon emissions are massive and can affect their sustainability. Therefore, optimising the environmental sustainability of these systems is necessary. Several studies have been proposed to mitigate this issue. However, the literature needs to include models for optimising the environmental sustainability of blockchain-based systems without compromising the fundamental properties inherent in blockchain technology. In this context, this thesis aims to optimise the environmental sustainability of blockchain-based systems by balancing different conflicting objectives without compromising the decentralisation and trustworthiness of the systems. First of all, we reformulate the problem of the environmental sustainability of the systems as a search-based software engineering problem. We represent the problem as a subset selection problem that selects an optimal set of miners for mining blocks in terms of four conflicting objectives: energy consumption, carbon emissions, decentralisation and trustworthiness. Secondly, we propose a reputation model to determine reputable miners based on their behaviour in a blockchain-based system. The reputation model can support the enhancement of the environmental sustainability of the system. Moreover, it can improve the system's trustworthiness when the number of miners is reduced to minimise energy consumption and carbon emissions. Thirdly, we propose a self-adaptive model that optimises the environmental sustainability of blockchain-based systems taking into account environmental changes and decision-makers' requirements. We have conducted a series of experiments to evaluate the applicability and effectiveness of the proposed models. Finally, the results demonstrate that our models can enhance the environmental sustainability of blockchain-based systems without compromising the core properties of blockchain technology