In this final domain, we turn our focus to troubleshooting—a skill that ties together everything you’ve learned so far. This episode introduces Domain 5 and outlines the key areas it covers, including troubleshooting methodology, cable testing, routing diagnostics, wireless issues, and performance analysis. Unlike previous domains that focused on setup and design, this one is about identifying and fixing what’s already built. If Domain 2 was implementation and Domain 3 was operation, this domain is where the rubber meets the road.

You’ll also be introduced to common tools, processes, and structured methods that help you logically step through a network issue. The goal is not just to guess the fix, but to isolate the problem, test assumptions, and document your actions. This is the real-world part of networking—where things go wrong and you make them right.