Which of the following works at the network layer and hides the local area network IP address and
topology?

A.
Network address translation (NAT)

B.
MAC address

C.
Hub

D.
Network interface card (NIC)

Explanation:
Network address translation (NAT) works at the network layer and hides the local area network IP
address and topology. Network address translation (NAT) is a technique that allows multiple
computers to share one or more IP addresses. It is configured at a server between a private network
and the Internet. It allows the computers in the private network to share a global, ISP assigned
address. It modifies the headers of packets traversing the server. For the packets outbound to the
Internet, it translates the source addresses from private to public, whereas for the packets inbound
from the Internet, it translates the destination addresses from public to private.

Answer B and D are incorrect. The MAC address and the network interface card (NIC) work at the
data link layer.

Answer C is incorrect. A hub works at the physical layer.