What is the bit length and format of the ARP broadcast destination?

What is the bit length and format of the ARP broadcast destination?

• A. 32-bit
• B. 128-bit
• C. 48-bit / 6-byte
• D. 64-bit

Answer: (C)

ARP broadcasts on Ethernet go to the MAC broadcast address, which is 6 bytes long (48 bits). The destination is FF:FF:FF:FF:FF:FF, targeting all devices on the local network segment. So the ARP broadcast destination is 48-bit / 6-byte. Note that the IP address ARP resolves is IPv4 (32 bits), but that IP length is separate from the link-layer destination; ARP operates at the link layer to map IPv4 addresses to MAC addresses.

ARP broadcasts on Ethernet go to the MAC broadcast address, which is 6 bytes long (48 bits). The destination is FF:FF:FF:FF:FF:FF, targeting all devices on the local network segment. So the ARP broadcast destination is 48-bit / 6-byte. Note that the IP address ARP resolves is IPv4 (32 bits), but that IP length is separate from the link-layer destination; ARP operates at the link layer to map IPv4 addresses to MAC addresses.