How cable, interface, and wireless diagnostic tools provide evidence for physical and local-network faults.
Choose a diagnostic tool that matches the fault boundary. Prove a dead cable or wireless channel problem before using higher-layer commands that require a working connection.
| Tool | Primary use |
|---|---|
| Cable tester | Continuity, pinout, or termination problems in copper cabling |
| Crimper | Attaching a connector to suitable cable |
| Punchdown tool | Seating conductors in a patch panel or keystone jack |
| Tone generator and probe | Identifying a cable run in a bundle or wall |
| Loopback plug | Testing a local interface path |
| Wi-Fi analyzer | Observing signal, channel use, and interference conditions |
For a dead wall jack, inspect the link, trace the run when necessary, and test the cable or termination. For a connection with a healthy link but no usable network access, inspect IP configuration, gateway reachability, and DNS. A Wi-Fi analyzer is appropriate for coverage or channel contention, not for a failed Ethernet termination.