I. Introduction
Since the Internet of things (IoT) technology was formally proposed by the International Telecommunication Union in 2005, it has been widely used in intelligent transportation, smart home, public safety, and many other aspects. However, the openness and extensiveness of the Internet of Things make the security issues of the Internet of Things more prominent. Common attacks against the Internet of Things include Distributed Denial of Service (DDoS) attacks, man-in-the-middle attacks, malicious implantation of backdoors, etc.