What will happen if a private IP address is assigned to a public interface connected to an ISP?
Answer: B. Addresses in a private range will not be routed on the Internet backbone.
When a device with a private IP address is connected to the Internet through a public interface, the IP address will be considered invalid because private IP addresses are not routable on the Internet backbone. This is because private IP addresses are reserved for use within private networks and are not unique on the public Internet. If a private IP address is used on a public interface, any traffic sent to that address will not be routed across the Internet, and any responses will not be able to find their way back to the source. This will result in a complete lack of connectivity to the Internet.
To connect to the Internet, devices must use public IP addresses, which are globally unique and routable on the Internet backbone. To address the problem of private IP addresses being used on public interfaces, Network Address Translation (NAT) is often used. NAT allows multiple devices on a private network to share a single public IP address. The NAT process translates the private IP addresses of devices on the private network to the public IP address assigned to the public interface of the router. When the router receives traffic from the Internet, it uses the NAT process to translate the destination IP address of the traffic to the appropriate private IP address on the private network. This allows devices on the private network to access the Internet using a single public IP address.