Abstract:With the rapid development of the Internet of Things (IoT), the number of smart devices has increased sharply, and identity authentication becomes the primary requirement for ensuring IoT security. Blockchain, as a distributed ledger technology, provides a trusted collaboration environment and a secure data management platform. The utilization of blockchain technology to drive IoT authentication has been a hotspot in academia and industry. This study analyzes the main requirements of authentication mechanism design based on cloud computing and cloud-edge collaboration and summarizes the challenges in applying blockchain technology to IoT scenarios. Relevant research on IoT authentication mechanisms is presented and classified into three categories of key-based authentication, certificate-based authentication, and identity-based authentication. Moreover, the existing IoT authentication studies using blockchain technology are analyzed, and related literature is reviewed according to authentication objects and additional attributes. This study also summarizes the security analysis method for the blockchain-based IoT authentication mechanism from formal and informal perspectives and finally points out the prospect of the technology.