The Internet of Things increases the facility by which data from digital devices can be gathered, analyzed, and perfected in numerous disparate industries. IoT, however, exposes several types of security violations, including compromise of trust, confidentiality, integrity, and resource availability. Among these, Distributed Denial of Service (DDoS) attacks are the most prevalent. They are the flooding of communication channels with networks under subjection to attacks indistinguishable from multiple IoT devices, these attacks yield the network resource availability. This chapter provides a deep insight into IoT, the security vulnerabilities of IoT, DDoS attacks on IoT systems, the types of these attacks, the vulnerabilities existing regarding where they can be conducted, and the usage of these IoT devices to create botnets. Also, it discusses in depth how AI and blockchain can be used as controls for preventing attacks. It also offers a comparative analysis and looks at the latest DDoS defense strategies for assistance in understanding. This chapter also includes an in-depth overview of IoT, including its applications, architecture, and componentry, with a focus on the projected increase of 30 billion connected devices by 2020.