FS163 is a draft document published by the Internet Engineering Task Force's (IETF) Security Area’s Security Services Architecture Committee (SSAC). It provides guidance on designing security services in Internet Protocol (IP) networks. FS163 outlines security requirements, security goals, and security architectures for IP networks, focusing on firewall-based security. It provides a comprehensive set of security service recommendations, including user authentication, access control, network security traffic monitoring, and private network access. FS163 also analyzes the risk to a network of not employing the services, provides security recommendations based on the analysis, and outlines best practices for deploying a secure network.