What is IPsec?

• A. A VPN client for remote desktop.
• B. A firewall rule management utility.
• C. A secure network protocol suite that authenticates and encrypts data packets for secure communication over IP networks, used in VPNs.
• D. A web server vulnerability scanning tool.

Answer: (C)

IPsec is a secure network protocol suite that authenticates and encrypts data packets for secure communication over IP networks, and is commonly used to build VPNs. It provides confidentiality, integrity, and authentication for IP traffic. IPsec can operate in transport mode, protecting the payload of individual packets, or in tunnel mode, wrapping entire packets to connect networks or gateways. It uses AH for data integrity and authentication, and ESP for encryption (often combining both). Key management is handled by Internet Key Exchange (IKE), which negotiates security associations and keys. In short, IPsec secures data as it travels over untrusted networks, making it a foundational technology for VPNs. It’s not a VPN client, a firewall rule utility, or a vulnerability scanner.