1. Know the path a packet takes
Follow traffic from source to destination. Learn what your endpoint, switch, router, firewall, and DNS resolver each contribute.
2. Understand the important addresses
An IP address tells you where traffic is routed; a MAC address matters on the local segment. Private address ranges and NAT explain why one user may appear behind a shared public address.
3. Learn DNS before memorizing ports
DNS turns names into records, and its answers can reveal where a system is trying to go. Start with A, AAAA, CNAME, and TXT records.
4. Read the shape of a connection
A TCP handshake is a conversation. A timeout, reset, or completed session can each tell a different story.
5. Get comfortable with logs
Timestamps, source, destination, protocol, and action are the building blocks. Practice connecting events across devices instead of reading one log in isolation.