The Fourth Industrial Revolution, or Industry 4.0, is all about digital transformation, manufacturing, and production. The connected world we live in today, including industries, comes with several cybersecurity challenges that need immediate attention. This book takes you through the basics of IoT and OT architecture and helps you understand and mitigate these security challenges. The book begins with an overview of the challenges faced in managing and securing IoT and OT devices in Industry 4.0. You’ll then get to grips with the Purdue model of reference architecture, which will help you explore common cyber attacks in IoT and OT environments. As you progress, you’ll be introduced to Microsoft Defender for IoT and understand its capabilities in securing IoT and OT environments. Finally, you will discover best practices for achieving continuous monitoring and vulnerability management, as well as threat monitoring and hunting, and find out how to align your business model toward zero trust. By the end of this security book, you’ll be equipped with the knowledge and skills to efficiently secure IoT and OT environments using Microsoft Defender for IoT.