Which of the following protects against unauthorized access to confidential information via encryption and works at the network layer?

Which of the following protects against unauthorized access to confidential information via
encryption and works at the network layer?

A.
Firewall

B.
NAT

C.
IPSec

D.
MAC address

Explanation:
Internet Protocol security (IPSec) protects against data manipulation and unauthorized access to
confidential information via encryption and works at the network layer.
IPSec provides machine-level authentication as well as data encryption. It is used for VPN
connections that use the L2TP protocol. It secures both data and password.

Answer B is incorrect. NAT also works at the network layer, but it does not provide encryption for
data.