Network Defense Essentials (NDE) Practice Exam

Which network security protocol is responsible for authentication and encryption in VPNs?

1. SSL/TLS

2. IPsec

3. L2TP

4. WireGuard

The correct answer is: IPsec

The selection of IPsec as the network security protocol responsible for authentication and encryption in VPNs is based on its comprehensive capabilities. IPsec, or Internet Protocol Security, operates at the network layer and is designed to secure Internet Protocol (IP) communications by authenticating and encrypting each IP packet within a communication session. This dual functionality ensures that data transmitted across a VPN remains confidential and helps verify the identity of the communicating parties. IPsec provides various modes of operation, including transport mode, which encrypts only the payload of the IP packet, and tunnel mode, which encrypts the entire IP packet. This flexibility allows it to be implemented in a wide range of applications, frequently serving as the backbone for VPN technologies. While other protocols like SSL/TLS and WireGuard also focus on security, they typically apply to different layers of the network stack or encompass different methodologies in their implementations; for instance, SSL/TLS works primarily at the transport layer and is commonly associated with securing web traffic rather than being a native VPN protocol. L2TP, on the other hand, is often paired with IPsec for encryption but does not itself provide encryption or authentication. Hence, IPsec stands out as a dedicated solution for both authentication and encryption in VPN scenarios.