Episode 7 — Prove network segmentation truly isolates the CDE
This episode teaches the difference between “we have segmentation” and “we can prove segmentation,” which is a central ISA exam skill and a frequent real-world failure point. You’ll define segmentation objectives, including limiting access paths into the cardholder data environment and reducing the number of systems in scope, then you’ll learn what evidence demonstrates isolation in a defensible way. We’ll cover common segmentation patterns, such as VLANs with firewalls, microsegmentation, jump hosts, and restricted management networks, and we’ll discuss how each pattern can fail through misconfigurations, shared services, permissive rules, or uncontrolled admin access. You’ll also learn what assessors look for in rule reviews, network diagrams, device configs, and testing results, and how to document exceptions without weakening your position. Troubleshooting scenarios will include rogue routes, overly broad firewall objects, and “temporary” rules that never get removed, along with practical steps for validating and tightening boundaries. Produced by BareMetalCyber.com, where you’ll find more cyber audio courses, books, and information to strengthen your educational path. Also, if you want to stay up to date with the latest news, visit DailyCyber.News for a newsletter you can use, and a daily podcast you can commute with.
