A Systematic Analysis on Blockchain Consensus Algorithms and Security Threats

Blockchain is a new technology which is basically used for store and verified transactions of cryptocurrency like Bitcoin, Ethereum etc. It is a digital, distributed, decentralized and immutable ledger. Transactions in Blockchain always store after verified by multiple validators in peer-to-peer network by using consensus algorithms like Proof of Work (PoW), Proof of Stake (PoS) etc. In blockchain there is no third party involved or managed the transactions. This paper elaborates the basics of Blockchain, its digital transactions in multiple areas like Internet of Things, Education, Manufacturing and financial services, characteristics and limitations of consensus algorithms, gave technical guidance for a suitable consensus algorithms and further areas of research.