How public and local addresses differ, how NAT works, and what CGNAT and IPv6 change.

How it works in practice

Treat this topic as part of the complete connection path, not as an isolated command or term. Record the starting conditions, measure the result, and only then change configuration. That order reduces false conclusions.

A diagnostic workflow

1. Define expected behavior and the exact test target.
2. Collect evidence from two independent locations or sources.
3. Compare timing, path, errors, and configuration changes.
4. Repeat the measurement after the fix and keep the result.

Check it with Net Utils

Use the relevant Net Utils tool and compare the structured output with your expected configuration. Public network data changes, so confirm important conclusions with a repeat test.