Perimeter defenses guarding your network aren't as secure as you might think. Hosts behind the firewall have no defenses of their own, so when a host in the "trusted" zone is breached, access to your data center is not far behind. This practical book introduces you to the zero trust model, a method that treats all hosts as if they're internet-facing, and considers the entire network to be compromised and hostile. In this updated edition, the authors show you how zero trust lets you focus on building strong authentication, authorization, and encryption throughout, while providing compartmentalized access and better operational agility. You'll learn the architecture of a zero trust network, including how to build one using currently available technology. You'll also explore fundamental concepts of a zero trust network, including trust engine, policy engine, and context aware agents; discover how this model embeds security within the system's operation, rather than layering it on top; use existing technology to establish trust among the actors in a network; migrate from a perimeter-based network to a zero trust network in production; examine case studies that provide insights into various organizations' zero trust journeys; and learn about the various zero trust architectures, standards, and frameworks.