Which Layer 2 protocol maps IP addresses to MAC addresses?

Which Layer 2 protocol maps IP addresses to MAC addresses?

• A. ARP
• B. ARP Table
• C. Routing
• D. Default Route

Answer: (A)

ARP translates an IP address to a MAC address on a local network. When a host needs to send an IPv4 packet to another device on the same LAN, it first checks its ARP cache for the corresponding MAC. If there’s no entry, it broadcasts an ARP request asking who has that IP, and the device with that IP replies with its MAC address. The requester then stores this mapping in the ARP table for quick use next time. This behavior is specific to IPv4; IPv6 uses Neighbor Discovery for a similar purpose. The other items refer to caches or routing actions, not the protocol that performs the address-to-MAC translation.

ARP translates an IP address to a MAC address on a local network. When a host needs to send an IPv4 packet to another device on the same LAN, it first checks its ARP cache for the corresponding MAC. If there’s no entry, it broadcasts an ARP request asking who has that IP, and the device with that IP replies with its MAC address. The requester then stores this mapping in the ARP table for quick use next time. This behavior is specific to IPv4; IPv6 uses Neighbor Discovery for a similar purpose. The other items refer to caches or routing actions, not the protocol that performs the address-to-MAC translation.