关键词: 区块链, 分布式账本, 共识机制, 智能合约, 区块链应用

Abstract: Blockchain is a kind of distributed ledger that combines time series data into a chain structure, and the crypto-
graphy guarantees transaction data to be tamper-resistant. It is a new distributed computing model and decentralized infrastructure. Blockchain technology has the characteristics of decentralization, trust building, collective maintenance, transaction fairness and transparency, tamper-resistant, and traceability. The research of blockchain has become a hot point in industry and academia. This paper introduces the main components of the blockchain, elaborates the basic principles of blockchain technology, smart contracts, consensus mechanisms and other key technologies. It provides a new and optimized direction for financial, Internet of Things, supply chain, and medical system applications. This paper summarizes the shortcomings of blockchain technology in terms of security, efficiency and privacy protection, and proposes effective methods for consensus mechanisms, anonymity issues and efficiency issues. That provides useful reference and guidance for the further development and improvement of blockchain technology.

Key words: blockchain, distributed ledger, consensus mechanism, smart contract, blockchain application