What is the primary purpose of the ARP protocol?

What is the primary purpose of the ARP protocol?

• A. To map IP addresses to MAC addresses on a local network.
• B. To resolve DNS names to IP addresses.
• C. To assign IP addresses via DHCP.
• D. To route packets between networks.

Answer: (A)

The primary purpose of ARP is to translate IPv4 addresses into MAC addresses on a local network so devices can actually reach each other at the data-link layer. When a host wants to send to another host on the same LAN, it checks its ARP table for the MAC address corresponding to the destination IP; if it’s missing, it broadcasts an ARP request asking who has that IP, and the owner replies with its MAC address, which the sender then caches for future use. This resolution happens only within a single network segment and ARP does not handle DNS name resolution, IP address assignment, or routing between networks. DNS maps names to IPs, DHCP assigns IP addresses, and routing moves packets across routers to reach different networks.

The primary purpose of ARP is to translate IPv4 addresses into MAC addresses on a local network so devices can actually reach each other at the data-link layer. When a host wants to send to another host on the same LAN, it checks its ARP table for the MAC address corresponding to the destination IP; if it’s missing, it broadcasts an ARP request asking who has that IP, and the owner replies with its MAC address, which the sender then caches for future use. This resolution happens only within a single network segment and ARP does not handle DNS name resolution, IP address assignment, or routing between networks. DNS maps names to IPs, DHCP assigns IP addresses, and routing moves packets across routers to reach different networks.