Definition
Security boundaries are logical or physical divisions that separate systems, networks, or data based on trust levels or access requirements. They act as barriers, controlling the flow of information and enforcing security policies between different zones. Implementing security boundaries is crucial for isolating sensitive assets, preventing the lateral movement of threats, and containing the impact of a security breach. For instance, a demilitarized zone (DMZ) serves as a security boundary between an organization's internal network and the public internet, hosting publicly accessible servers. A common point of confusion is mistaking security boundaries for simple network segmentation. boundaries imply stricter access controls and trust evaluation. This concept is fundamental to domains covered on exams like CompTIA Security+, CySA+, and CISSP.