Abstract: With the increasingly widespread application of blockchain technology, the research of blockchain technology has gradually become more and more important. Blockchain technology is a combination of multiple technology that use consensus mechanisms to solve the Byzantine general problem and prevent malicious attacks. It also uses digital signatures, hash calculations, and other cryptographic methods to ensure transaction security. Blockchain technology is therefore known for the trusted machine. This paper first elaborates on the typical blockchain technology architecture, then analyzes the security of blockchain technology in terms of block data structure, hash algorithm, digital signature, smart contract, etc. finally, it concludes the blockchain technology still faced security issues.

Key words: blockchain, cryptography, consensus mechanism, smart contract

摘要： 随着区块链技术应用越来越广泛，区块链技术的研究逐渐变得越来越重要．区块链技术是由多种技术组合而成，利用共识机制来解决拜占庭将军问题和防止恶意攻击，同时还使用数字签名、哈希计算等密码学方式确保交易安全，因此区块链技术被誉为信任的机器．首先对典型区块链技术架构进行了详细阐述，然后从区块数据结构、哈希算法、数字签名、智能合约等方面对区块链技术的安全性进行了详细分析，最后总结了区块链技术仍面临的安全性问题．

关键词: 区块链, 密码学, 共识机制, 智能合约