Which of the following pairs correctly represents two VPN types commonly used?

• A. PPTP VPN and L2TP VPN.
• B. SSH VPN and IPsec VPN.
• C. IPsec VPN and SSL/TLS VPN.
• D. SSL VPN and PPTP VPN.

Answer: (C)

Two widely deployed VPN types are IPsec VPN and SSL/TLS VPN. IPsec VPN operates at the network layer, securing IP packets as they travel between endpoints. It’s a staple for site-to-site tunnels and remote-access connections in many enterprises, using protocols like ESP for encryption and AH for authentication, with IKE used for negotiating keys. This makes it ideal for full-network connectivity and transparent security across a corporate boundary.

SSL/TLS VPN works at the application layer, often letting users connect through a standard web browser over HTTPS. It’s popular for remote access because it minimizes client software requirements and traverses firewalls easily, providing secure access to specific applications or portals rather than the entire network. It’s particularly flexible for quick deployments and fine-grained access control.

These two represent common, practical approaches in real networks: IPsec for broad network-level security and SSL/TLS for flexible, browser-friendly remote access. Other pairs include older or less universally deployed options (like PPTP, which has known security weaknesses) or configurations that pair L2TP primarily with IPsec rather than standing alone as a widely used separate VPN type, which is why they’re less representative of current practice.