АЛГОРИТМИ КОНСЕНСУСА БЛОКЧЕЙН СИСТЕМ

Blockchain technology relies on decentralized data management across various applications to ensure secure transactions. Consensus algorithms play a critical role in maintaining consistency and trust within decentralized environments, laying the groundwork for further exploration. This paper presents a simulation-based benchmarking framework for evaluating major consensus mechanisms Proof of Work (PoW), Proof of Stake (PoS), Proof of Authority (PoA), Proof of Capacity (PoC), Practical Byzantine Fault Tolerance (PBFT), Directed Acyclic Graph (DAG), and Proof of Biometric Uniqueness (PoBU). A MATLAB-based simulation environment integrated with Docker-emulated blockchain nodes was developed to measure performance across several parameters, including throughput, latency, energy consumption, finality probability, fault tolerance, and resource requirements. Results show that DAG achieves the highest throughput (1600 TPS) and lowest latency (0.8 s), while PoBU offers strong fault tolerance (50%) and energy efficiency (60 J/tx). PBFT and PoA provide ultra-fast confirmations with limited decentralization, whereas PoW demonstrate poor scalability and energy efficiency. These findings highlight the potential for a unified benchmarking framework for consensus mechanisms and provide practical insights for selecting consensus protocols for specific blockchain applications.

The article investigates the process of block formation in blockchain networks and the impact of node network architecture and consensus algorithms on their scalability and performance. Analysis of blockchain system scalability is important due to problems that arise when network load increases, particularly the increase in the number of block forks and transaction confirmation times. The research focuses on studying the impact of network delays and the choice of consensus algorithm on the performance and scalability of blockchain networks. The main attention is devoted to mathematical models that describe block formation, as well as the analysis of factors affecting transaction processing speed and throughput. The primary consensus algorithms, such as Proof of Work (PoW) and Proof of Stake (PoS), are considered, and their impact on scalability in implementations based on the Ethereum Virtual Machine (EVM) and Bitcoin is compared. Experimental studies using Geth and Amazon cloud services revealed that the application of the Proof of Stake (PoS) consensus algorithm increases network performance by reducing the complexity of the block formation process in blockchain networks by 99% and accelerates consensus achievement by 70% compared to Proof of Work (PoW). It was also established that increasing the number of nodes from 5 to 50 reduces the network's throughput by almost 10%, and the average confirmation time doubles. The obtained results are aimed at solving the scalability issue by reducing transaction confirmation times for the implementation of decentralized technologies in the Internet of Things (IoT) sphere, where processing speed and storage of large volumes of data are critically important. Keywords: blockchain, block formation, consensus algorithms, decentralized technologies, Ethereum Virtual Machine (EVM), Internet of Things (IoT), mathematical modeling, network delays, scalability.

As the basis of the most existing blockchain networks, Proof of Work (PoW) consensus protocol highly relies on the computational resources, and thus causing a huge waste of energy. Proof of Stake (PoS) is the alternative to relieve the PoW dilemma. However, it is also under threat, i.e., discouragement attack, which is a way to bring down the blockchain networks without any effective defense against it. To prevent the discouragement attack, the founders of Ethereum argue that the system should set a withdraw delay instead of allowing the validators entry/exit quickly. But how to determine the delay is still an open question. In this paper, we adopt the cyber insurance idea and propose the insurance contract to help determine the withdraw delay, as well as the insurance claim to relieve the loss of victims. Specifically, instead of requiring the insurance premium from the validators, the cyber insurer first signs the contract with the blockchain representative (e.g., beacon chain). Then the blockchain representative would sign a series of contracts with the validators. By such design, the validators can obtain the insurance claim without paying the premium, while the blockchain networks can keep the validators staying online to resist the discouragement attack. Finally, through the simulations, we demonstrate that the proposed model is capable of providing adaptive insurance contracts for the different validators and keeping the profits of the blockchain network and the cyber insurer.

This research document demonstrates the understanding of two key elements: Proof of Work (PoW) and Proof of Stake (PoS) within cryptocurrency. Cryptocurrency is often misunderstood as just volatile and risky but many investors do not understand what it even is. What is proof of work (BTC)? What is proof of stake (ETH)? How are they similar and how are they different? Cryptocurrency is actually more relatable that originally imagined once a person understands digital currency, money, it’s origins, and how they hold similar monetary value within their own wallets. Cryptocurrency in PoW involves complicated mathematical equation solving via mining from a large growing pool of miners. These miners receive rewards such as bitcoin/tokens/etc. from their mined hash blocks verified, and blocks added to the blockchain. Challenges are that there are many miners and there may be a computational limit per core of each PC to be able to mine since Bitcoin has increased its difficulty 70 billion times since it started. BTC or Bitcoin is still widely trusted due to its increasing difficulty to race to the finish line to finish the advanced math computations. Whereas within PoS this is not a race between the masses and advanced math computations, but a validator that generally has more put in their stake vs. gained by receiving the processing fees associated. ETH or Ethereum has shifted from PoW to PoS for its better energy efficiency in resources. It has employed many other additional checks from Casper to Gasper which is the combination of Casper (fork-choice algorithm), LMD-GHOST (heavest observed subtree), and finality which requires 2/3rd agreement as well as once a block is justified it is upgraded to a finalized block. the similarities between the two PoW and PoS are that they are consensus-driven algorithms. They are designed to reach an agreement between the systems in place before each block is placed in the blockchain. Additionally, they also have a shared public ledger that operates on a global if not international scale. With blockchains, there is always only one true version and this is relying on a network rather than a governing authority like a bank/government entity to provide security and to prevent fraudulent transactions. It is still widely contested which is better than these two well-known consensus algorithms and it is still widely contested. The best answer is suited on a per investor per business basis in terms of the willingness of taking a risk just like any investment. This document serves to help provide guidance in the understanding of cryptocurrency of two main consensus algorithms, its similarities, differences, and help identify see what a potential investor the reader may be.

Blockchain technology has become one of the most disruptive innovations of the 21st century, reshaping industries such as finance, supply chain management, healthcare, and governance. However, the conventional blockchain ecosystem—particularly models based on Proof of Work (PoW)—has been widely criticized for its excessive energy consumption and ecological footprint. As societies move toward sustainability and carbon-neutral goals, the exploration of energy-efficient blockchain models becomes not just an academic pursuit but also an ethical imperative. This manuscript investigates the evolution of energy-efficient consensus mechanisms and their integration into “green smart contracts,” which enable automated, verifiable, and sustainable digital agreements. It highlights consensus algorithms such as Proof of Stake (PoS), Delegated Proof of Stake (DPoS), Proof of Authority (PoA), Proof of Space-Time (PoST), Practical Byzantine Fault Tolerance (PBFT), and emerging hybrid mechanisms. The manuscript offers a comprehensive literature review, outlines statistical insights comparing energy and performance trade-offs, and proposes methodologies for integrating eco-friendly smart contract architectures. The results emphasize that while PoW-based systems consume up to 99% more energy than PoS-based models, hybrid approaches demonstrate a promising balance between security, decentralization, and efficiency. The study concludes that energy-efficient blockchain models, when strategically aligned with sustainability frameworks, can redefine smart contract ecosystems to meet global climate commitments while maintaining reliability, transparency, and scalability.

eBCTC: Energy-efficient hybrid blockchain architecture for smart and secured K-ETS

Cryptocurrency mining, especially Bitcoin's Proof of Work (PoW), significantly impacts the environment through high energy consumption, carbon footprint, and e-waste. Ethereum's adoption of Proof of Stake (PoS) in 2022 offers a potential solution to reduce these effects. This study compares the environmental impacts of PoW and PoS, focusing on energy consumption, mining efficiency, hash rate, and carbon footprint. Using regression analysis and t-tests on data from Bitcoin (PoW) and Ethereum (before and after PoS) from 2017 to 2024, the results show that PoS significantly reduces energy consumption, carbon footprint, and e-waste, while improving mining efficiency. The findings highlight that transitioning to PoS can mitigate the environmental impact of cryptocurrency mining and encourage its broader adoption to align with global sustainability goals.

The arrival of the Proof of Stake (POS) consensus algorithm has solved the problem of energy waste caused by Proof of Work (POW) through replacing POW’s wasteful computing power with proof of possession of a certain amount of locked token called “Stake”. The weight of the latter will allow its holder to be more likely to be selected as “Leader” and earn a corresponding reward. However, the mechanism adopted by POW, the POS (and its derivatives) promotes the mining monopoly by the most powerful or the wealthiest members of the network without any other tangible criterion proving that these participants actively contribute to the security of the Blockchain network and respect the security recommendations (application of urgent updates for example) issued by the development team of said Blockchain.In this paper, we propose a new consensus algorithm called “Proof of Conformity -PoC-” favoring the node security aspect and offering additional reliability to the Blockchain. Proof of Conformity improvement involves the introduction of a new impact factor in the node weight calculation named “Node Security Metric” (NSM).NSM is primarily based on the Common Vulnerability Scoring System (CVSS). Furthermore, NSM computation mainly relies on the re-calculation of the weight of each network node based on the stability and security of their software and hardware environment. Our new approach will strengthen the node security index and encourage miners with up-to-date environments. Moreover, compliant, proactive and vigilant nodes will increase their chances of being selected as “Leader” and earning rewards.PoC is theoretically evaluated through simulation scenarios and the result obtained shows that our approach ensures that participating nodes deemed secure are more likely to be designated as “Leader” based on their conformity rates reflected by their NSM score.KeywordsBlockchainConsensus algorithmCVSSDistributed systemSecurityProtocolsDecentralised system

As approaching the era of Ethereum 2.0, the already unique and innovative cryptocurrency will witness a game-changing upgrade, and in this context, there is a lively discussion of the Proof of Work (PoW) and Proof of Stake (PoS) consensus mechanism. Moving from a PoW consensus mechanism to a PoS consensus mechanism is one of the most anticipated changes in this update. A close comparison of the two most popular consensus mechanisms, PoW and PoS, provides some strengths and drawbacks to these mechanisms. This comparison then becomes the building block to identifying the reasons behind Ethereum's upgrade to Proof of Stake. With the help of the comparison, this paper identifies a few drawbacks of the PoW consensus mechanism that Ethereum is currently facing. This paper finds that Ethereum's shift to PoS has indeed reduced the drawbacks of the Proof of Work consensus mechanism, mainly in terms of energy consumption, transaction cost, and confirmation speed.

Traditional blockchain consensus mechanisms, such as Proof of Work (PoW) and Proof of Stake (PoS), face significant challenges related to the centralisation of validators and miners, environmental impact, and trustworthiness. While PoW is highly secure, it is energy-intensive, and PoS tends to favour wealthy stakeholders, leading to validator centralisation. Existing mechanisms lack fairness, and the aspect of sustainability is not considered. Moreover, it fails to address social trust dynamics within validator selection. To bridge this research gap, this paper proposes Proof of Friendship (PoF)—a novel consensus mechanism that leverages social trust by improving decentralisation, enhancing fairness and sustainability among the validators. Unlike traditional methods that rely solely on computational power or financial stakes, PoF integrates friendship-based trust scores with geo-location diversity, transaction reliability, and sustainable energy adoption. By incorporating a trust graph, where validators are selected based on their verified relationships within the network, PoF mitigates the risks of Sybil attacks, promotes community-driven decentralisation, and enhances the resilience of the blockchain against adversarial manipulation. This research introduces the formal model of PoF, evaluates its security, decentralisation, and sustainability trade-offs, and demonstrates its effectiveness compared to existing consensus mechanisms. Our investigation and results indicate that PoF achieves higher decentralisation, improved trustworthiness, reduced validator monopolisation, and enhanced sustainability while maintaining strong network security. This study opens new avenues for socially aware blockchain governance, making consensus mechanisms more equitable, efficient, and environmentally responsible. This consensus mechanism demonstrates a holistic approach to modern blockchain design, addressing key challenges in trust, performance, and sustainability. The mechanism is tested theoretically and experimentally to validate its robustness and functionality. Processing latency (PL), network latency (NL) [transaction size/network speed], synchronisation delays (SDs), and cumulative delay per transaction are 85 ms, 172 ms, 1802 ms, [PL + NL + SD] 2059 ms, respectively.

Healthcare Blockchains (HBC) are grooming nowadays due to the requirements of flexible Electronic Health Records (EHR) management, privacy needs, and controlled medical data access. Blockchain technology very much suits these requirements and support in various healthcare data access control methods. More focus on improved block generation time gives the expected blockchain performance. Block generation time can be significantly improved by the consensus algorithms used by the system. Traditional consensus algorithm of Proof of Work (PoW) and Proof of Stake (PoS) require heavy computational resources and hence by computational overheads. The proposed system introduces a new privacy-preserving HBC consensus protocol as a consequence of member attribute values and significantly reduced computational resources. The new attribute-based consensus algorithm for HBC called Proof of Policy (PoP) is constructed using Attribute-Based Ring Signature (ABRS). This signature agrees on the stake of attribute-based ring membership and can be considered as an extension of Proof of Stake (PoS). It is also found that the proposed PoP consensus algorithm requires less computational resources than popular PoW and PoS.

Applying Blockchain consensus mechanisms to Network Service Federation: Analysis and performance evaluation

Blockchain-based technologies have been created across a range of businesses for improving data security and integrity. A network chain is the most remarkable blockchain applications as part of the Industrial Internet of Things (IIoT). Sensor data in real time aids industrial equipment and infrastructures in making decisions and taking specified actions. Without sufficient security, an IIoT system can cause operational disruption and financial loss and lead to malicious activities and system manipulation. Detecting anomalies in IIoT networks is critical for network security. In this paper we discuss the Proof of Authority consensus algorithm. The Proof of Authority (PoA) depends on the reputation of trusted parties in blockchain network. The PoA consensus mechanism is based on the values of identities on a network, and validators stake their own identities and reputation. So, the validating nodes that are randomly picked as trustworthy safeguard the Proof of Authority Blockchain network. In Proof of Authority model, transactions are reviewed by already approved network users, and it operates with a fixed number of block validators. Since the identities of the nodes are trusted and known, the process can be used in applications like supply chains and trade networks.

In the white book of Bitcion, Satoshi Nakamoto described a bitcoin system that can realize point-to-point online payment without a third-party organization. After supporting this magical application scenario and subverting the traditional centralized system, the blockchain technology has attracted worldwide attention, triggered a research upsurge of blockchain consensus algorithm, and produced a large number of innovative applications. Although various consensus algorithms continue to evolve with the iteration of blockchain products and applications, Proof of Work (POW) and Proof of Skake (POS) algorithms are still the core of consensus algorithms. This paper discussestwo algorithms of POW and POS in blockchain consensus mechanism, and analyzes the advantages and the existing problems of the two consensus mechanisms. Since consensus mechanism is the main focus of blockchain technology and has many influencing factors, this paper discusses the current problems and some improved ideas, and selectes some typical algorithms for a more systematic introduction. In addition, some important issues related to safety and performance are also discussed. This paper provides the researchers a great reference on blockchain consensus mechanism.

Many researchers are studying the applications that ensemble blockchain and IoT. In such applications, a blockchain is normally deployed on top of the infrastructure-based underlying IoT network (e.g., Wi-Fi), which incurs the single point of failure issue. This work considers using infrastructure-less IoT for blockchain (i.e., ad-hoc IoT-blockchain network) to avoid the issue. Like in other networks, latency is one of the essential parameters to assess the network quality in the ad-hoc IoT -blockchain system. The latency is inherently related to the synchronization of transactions and blocks messages in the blockchain. Therefore, latency evaluation in an ad-hoc IoT-blockchain network is necessary. This research evaluates two latency metrics named Transaction-Oriented Latency (TOL) and Block-Oriented Latency (BOL) in an ad-hoc IoT-Blockchain system with Ethereum and two well-known consensus mechanisms: Proof of Work (PoW) and Proof of Authority (PoA). We create a smart contract that the different number of transactions can trigger; we then adopt the measurement method of the latency values. The evaluation results reveal the TOL and BOL following the transaction number in both the ad-hoc IoT-blockchain with PoA and PoW.