https://www.youtube.com/watch?v=jhXCTbFnK8o

https://www.youtube.com/watch?v=NuyzuNBFWxQ&t=6s

DOMAIN 3 Walk-Through

How security is built into systems from the very beginning

The Mindset of Domain 3

Domain 3 is about architecture —

designing systems so that even if an attacker gets in, they can’t go far.

1. Zero Trust Architecture

Assume nothing is trustworthy by default.

• every request is authenticated
• every device is validated
• every connection is verified
• every access is checked for privilege

This is real-world architecture, not theory.

2. Defense in Depth

Build multiple layers:

• physical security
• network segmentation