I. Introduction
Since the International Telecommunication Union officially proposed the concept of Internet of Things (IoT)in 2005, technologies such as sensor networks, cloud computing, and microchips have matured over time, and the Internet of Things industry has also rapidly expanded. According to the latest statistics of the Statista portal, the number of connected devices has reached 17.6 billion in 2016 and is expected to exceed 30 billion by 2020. International Data Corporation predicts that the Internet of Things market will exceed $7 trillion by 2020. While the Internet of Things is developing at a rapid pace, its security is also facing severe challenges. At present, countries, enterprises and individuals have not established enough awareness of IoT security and privacy protection. The IoT security issue will not only bring property damage to users but also threaten the lives of users.