Blockchain technology has been generating great interest by a variety of industry sectors. Realizing the strength of blockchain technology beyond its successful application in the cryptocurrency arena, researchers have been evaluating and using blockchain for applications such as supply chain management, the energy industry, health sectors, and much more. Some of the features include smart contracts, decentralization, consensus, immutable distributed ledgers, cryptographic hashing, and digital signatures. There are multiple types of blockchain and different consensus models. However, it is often a significant undertaking to determine if an application requires a blockchain. What kind of blockchain and consensus model is best suited for a given scenario? This paper addresses this challenge by evaluating different blockchain solutions along with the consensus models to determine the applicability for different use cases. We propose a guideline and applicability analysis framework (AAF) to determine whether an application needs a blockchain solution or not. The AAF is divided into 6 domains, 11 subdomains, and 45 controls. It is designed to ingest detailed user requirements to perform a weighted evaluation that is built on mathematical constructs to determine the scenario in which a blockchain-based solution is appropriate. Moreover, this article also includes an example of evaluating applicability through AAF with the help of a use-case scenario.

Blockchain technology is extensively used for cryptocurrencies and is considered for industrial applications due to features like decentralization, anonymity, and a tamper-proof history of transactions. However, the well-known blockchain trilemma of being unable to simultaneously meet the properties of decentralization, security, and scalability (DSS) negatively impacts widespread acceptance. Numerous solutions have been put forward in response to this challenge, aiming to increase performance and scalability while retaining the decentralized and trustless aspects. They range from introducing off-chain technologies to changing consensus algorithms and on-chain data structures. One of the most effective methods to accomplish horizontal scalability along with the growing network size could be sharding, which involves dividing the network of nodes into numerous shards or channels. The overhead of repetitive communication, storage, and processing at each node is decreased by this technique. This paper explores various sharding approaches to solve performance issues regarding blockchain. We review recent sharding technologies, including Polkadot, Ethereum Casper, and Cardano Hydra. We discuss the performance challenges of blockchains and provide essential insights into the tradeoffs.

Conventional approaches to agreeing on transactions in monetary systems rely on trusted central authorities. Blockchain defies this model by achieving consensus through a community of peers in a decentralized network for validating transactions and maintaining an ordered record of transactions. The application domains for blockchain have expanded from cryptocurrencies to potentially any industrial system. However, there is still a lot of confusion regarding the advantage of using the blockchain instead of alternative technologies. The number of successfully deployed blockchain-based systems is still relatively small due to the lack of clarity regarding blockchain governance and the challenge of assessing the tradeoffs of blockchain-based solutions. As there are different types of blockchains, such as permissionless and permissioned, it often becomes hard to choose a suitable solution for a specific use case scenario. In this paper, we address these challenges by analyzing blockchain governance and related tradeoffs, including energy consumption, consensus, performance, and security. We contribute with a taxonomy guideline to provide insights on these tradeoffs and to facilitate effective identification of the suitable governance structure for blockchain-based solutions in various scenarios. The proposed taxonomy discusses different features of blockchain that includes energy consumption, consensus methods, performance, and security aspects to suggest the governance model (permissionless/permissioned/consortium) for a blockchain-based solution. Furthermore, this paper provides a tradeoff analysis of different consensus methods, such as PoW, PoS, PBFT, and PoA, considering important properties.

Blockchain is the underlying technology of a number of digital cryptocurrencies. Blockchain is a chain of blocks that store information with digital signatures in a decentralized and distributed network. The features of blockchain, including decentralization, immutability, transparency and auditability, make transactions more secure and tamper proof. Apart from cryptocurrency, blockchain technology can be used in financial and social services, risk management, healthcare facilities, and so on. A number of research studies focus on the opportunity that blockchain provides in various application domains. This paper presents a comparative study of the tradeoffs of blockchain and also explains the taxonomy and architecture of blockchain, provides a comparison among different consensus mechanisms and discusses challenges, including scalability, privacy, interoperability, energy consumption and regulatory issues. In addition, this paper also notes the future scope of blockchain technology.

Blockchain is a technology for storing an immutable history of transactions in a decentralized platform by using cryptographic principles. Many industries have become interested in adopting blockchain within their IT systems. However, the accessibility, privacy, performance, and scalability aspects of different blockchain-based platforms are still legitimate concerns when designing an enterprise solution. Permissioned blockchain frameworks facilitate a way to immutably store confidential records. Numerous research studies have been carried out on the opportunities, challenges, application areas, and performance analysis of different public and permissioned blockchain-based platforms. However, the implication of blockchain in recent private enterprise solution requires detailed comparative analysis. This paper conducts a performance and scalability analysis of popular private blockchain platforms, including Ethereum (private deployment), Quorum, Corda, and Hyperledger Fabric. Each of these platforms is assessed by varying the workloads (no. of transactions and nodes) and determining the performance evaluation metrics such as throughput and network latency.

Many countries in Europe are adopting a deregulated system where prosumers can subscribe with any energy supplier in an open market, independently of location. However, the mobility aspect of transactions in the existing system is not satisfactorily covered. For instance, if a person receives the service of charging an EV from a prosumer’s local outlet, he cannot pay to the prosumer directly without the presence of an intermediary system. This has led to a situation where the EV owners need to have a large number of subscriptions for EV charging providers and visitors cannot pay for the electricity used there. This study evaluates this mobility gap and proposes a solution for charging transactions using blockchain technology. Furthermore, we implement a proof of concept using the Hyperledger consortium platform for the technical feasibility of the proposed approach and evaluate the performance metrics such as transaction latency and throughput.