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ARP maps local IP addresses to devices’ MAC addresses

benjcal.space Editor score 6/10

The guide uses arp-scan to list devices on a local network and explains why IP and MAC addresses both matter. It’s a practical refresher on the networking basics beneath larger systems.

What: - ARP maps a local network device's IP address to its MAC address so a computer can send it data.
How: - A computer broadcasts an address query; the matching device replies with its MAC, which the computer can use to send a ping.
Why it matters: - Engineers need both addresses for local delivery: switches forward frames by MAC, while ping takes an IP address.

ARP broadcasts an address query and returns the matching device's MAC address. Sketched from the article's own text.

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