Which technology allows a large number of private IP addresses to be represented by a smaller number of public IP addresses?

The technology that allows a large number of private IP addresses to be represented by a smaller number of public IP addresses is Network Address Translation (NAT). NAT works by enabling multiple devices on a local network to share a single public IP address when accessing the internet. This is particularly beneficial for conserving the limited number of available public IP addresses.

In practice, NAT translates the private IP addresses of internal devices to the public IP address of the router as traffic passes to and from the internet. This allows devices within a private network—such as computers, printers, and smartphones—to communicate externally while maintaining unique private IP addresses, thus significantly reducing the demand for public IPs.

RFC 1631 is the document that originally described NAT and its functions, but it is the implementation of NAT itself that actually provides the address conservation feature. RFC 1918 describes the specific ranges of IP addresses that are designated for private use, which are often used in conjunction with NAT, but does not perform any address translation by itself. NTP, or Network Time Protocol, has no relation to IP address utilization and is mainly used for synchronizing clocks between computer systems on a network.

Therefore, NAT is the technology that achieves the goal of allowing extensive private address use to be mapped