A Survey on Consensus Methods in Blockchain for Resource-constrained IoT Networks

Abstract

The success of blockchain as the underlying technology for cryptocurrencies has opened up possibilities for its use in other application domains as well. The main advantages of blockchain for its potential use in other areas are its inherent security mechanisms and immunity to data manipulation attacks. A blockchain relies on a consensus method for agreeing on any new data. Most of the consensus methods which are currently used for the blockchain of different cryptocurrencies require high computational power and thus are not suitable for resource-constrained systems. <div><br></div><div>In this article, we survey the various blockchain-based consensus methods that are applicable to resource-constrained IoT devices and networks. In a typical IoT network, there exist several devices with limited computational and communication capabilities. Most often, these devices cannot perform intensive computations and are starved for bandwidth. Therefore, we discuss the possible measures that can be taken to reduce the computational power and convergence time for the underlying consensus methods. We also talk about some of the alternatives to the public blockchain, such as private blockchain and tangle, along with their potential adoption for IoT networks. Furthermore, we review the existing consensus methods that have been implemented and explore the possibility of utilizing them to realize a blockchainbased IoT network. Some of the open research challenges including AI-enabled blockchains are also put forward. </div>

Consensus Algorithms Blockchain: A comparative study

“…PoET was introduced to address the problems of high-power consumption and latency in the PoW-based consensus protocols and to improve the efficiency of the mining process by following a fair lottery system [18], where every single node is equally likely to be a winner. PoET is similar to the proof of work [12] but with significantly lower energy (resource) consumption. According to this protocol, the miner node, which presents the least waiting time is selected to mine the next block; the timer is different for every node.…”

“…Leased proof of stake (LPoS) is another consensus algorithm which came to improve the degree of scalability and transaction throughput of the proof of stake protocol as this algorithm give the user the right to leased their coins to other trusted nodes. The larger the amount that is leased to all trusted node, the higher the chances of that node will be selected to produce the next block, If the node has validated the next block, the user would receive some part of transaction fees that are collected by the node [12] [15].…”

“…Blockchain consists of consecutive chained blocks, each one linked with the previous, containing records that has to reach a consensus before the contract is enacted [1] [3] [4].The consensus is a way to ensure the nodes on the network verify the transactions and agree with the order and existence on the ledger [5] [6]. In the case of applications like cryptocurrency, this process is critical so as to prevent double spending or other invalid data being written to the underlying ledger, which is a database of all the transactions [7] [8] The most widely used consensus algorithms are the Proof of Work (PoW) algorithm [1],the Proof of Stake (PoS) algorithm [9] [10] as well as Practical Byzantine Fault Tolerance (PBFT) algorithm [11];however, there are also other consensus algorithms which utilize alternative implementations of PoW, PoS and PBFT, as well as other hybrid implementations and some altogether new consensus strategies [12][13] [8].There are newer consensus mechanisms coming up every now and then, all of which are hoping to achieve the objectives of collaboration, egalitarianism and inclusion [14] [12].Consensus is used to create a more equal and fair society for users in the decentralized network from all around the world [15]. In this research, to design the comparative study based on selected factors, we present a new category of the Blockchain consensus algorithms, the classification consists of the following main groups (see fig1 )as follows; The first group is the proof based on Hardware which is by using computing power to translate into Hashing Power for the network ,this group includes POW, POET and POC.…”

A Survey on Decentralized Consensus Mechanisms for Cyber Physical Systems

“…PoM resolves these said issues and gives us good, trusted, closed, and controlled environment. All the miners try to mine the nodes in the single BC, so there is a security threat that one faulty chain can make the upcoming nodes faulty [120]. Zoican et al [15] evaluated and compared the computational effort required for the implementation of these consensus algorithms used for BC-based IoT applications.…”

Smart Contract Centric Inference Engine For Intelligent Electric Vehicle Transportation System

“…Every reading within the blockchain is timestamped and hard to tamper. Salimitari et al [31] performed a survey of consensus protocols in the blockchain. They mentioned that a blockchain-based system is reliable and strong as its base consensus system, and hyper ledger fabric uses a practical Byzantine fault tolerance consensus method suitable for private blockchain.…”