Port address translation (PAT), also known as NAT overload, maps multiple private IP addresses to a single public IP address or a few addresses. It does this by keeping track of ports to distinguish between different connections. Different port assignments allow multiple connections to be uniquely identified, even though they share the same public IP. Static NAT would not be appropriate in this case because it maps a single private IP address to a single public IP address, which does not support multiple hosts simultaneously. Dynamic NAT would require a pool of public IP addresses for multiple hosts, which doesn't match the requirement of using only one public IP. DHCP is used for automatic IP addressing within a local network and does not facilitate Internet access through a single public IP address.