Which technology enables devices with private IP addresses to communicate with public Internet resources by translating addresses?

• A. NAT
• B. DNS
• C. DHCP
• D. ARP

Answer: (A)

Address translation that lets devices with private IP addresses reach public Internet resources is accomplished by NAT. NAT sits at the network edge and rewrites the source address (and often the source port) of outgoing packets from a private IP to a public IP assigned to the router or gateway. This mapping lets many devices share a single public address while their responses are routed back through the NAT device, which then translates the public destination back to the correct private host.

Why this works: private IPs aren’t routable on the public Internet, so a translation layer is needed to bridge private networks and the wider Internet. NAT maintains a translation table to track each active connection and ensures responses reach the correct internal device.

DNS, DH​CP, and ARP don’t provide this kind of cross-network address translation. DNS converts domain names to IP addresses; DHCP assigns IP addresses within a local network; ARP maps IP addresses to MAC addresses on a local link.