随着物联网（Internet of Things，IoT）技术的高速发展，各类智能设备数量激增，身份认证成为保障IoT安全的首要需求.区块链作为一种分布式账本技术，提供了去信任的协作环境和安全的数据管理平台，使用区块链技术驱动IoT认证成为学术界和工业界关注的热点.基于云计算和云边协同两种架构分析IoT身份认证机制设计的主要需求，总结区块链技术应用于IoT场景面临的挑战；梳理现有IoT身份认证机制的工作，并将其归结为基于密钥的认证、基于证书的认证和基于身份的认证；分析应用区块链技术的IoT认证工作，并根据认证对象和附加属性对相关文献进行归纳和总结.从形式化和非形式化两个方向总结基于区块链的IoT认证机制的安全性分析方法.最后展望了未来研究方向.
With the rapid development of the Internet of Things (IoT), the number of various smart devices has increased sharply, and identity authentication has become the primary requirement for ensuring the security and credibility of IoT. Blockchain, as a distributed ledger technology, provides a trusted collaboration environment and a secure data management platform. The use of blockchain technology to drive IoT authentication has become a hot spot in academia and industry. This article analyzes the main requirements of authentication mechanism design based on cloud computing and cloud-edge collaboration. The challenges in applying blockchain technology to IoT scenarios are pointed out. The works on IoT authentication mechanisms are collected and classified into three categories:key-based authentication, certificate-based authentication, and identity-based authentication. Moreover, the existing IoT authentication works using blockchain technology are analyzed comparatively. The relevant documents are categorized and discussed according to authentication objects and additional attributes. We summarize the security analysis method for the blockchain-based IoT authentication mechanism from both formal and informal perspectives. Finally, we look into the future of the field.