This document outlines the zero trust network (ZTN) model as an alternative to traditional network security models. It discusses the problems with assuming network traffic is trusted within an organization's perimeter, as well as the key concepts and components of a ZTN architecture, which are that all network traffic is untrusted, access is granted based on dynamic policy evaluation, and strict identity-based access controls are implemented. The document provides recommendations for implementing ZTN architectures focused on network segmentation, advanced network security controls, and strong data-level security.