IPsec provides two encryption modes: Tunnel mode and Transport mode. Which option reflects that statement?

IPsec provides two encryption modes: Tunnel mode and Transport mode. Which option reflects that statement?

• A. Tunnel mode and transport mode
• B. Data link mode and network mode
• C. User mode and kernel mode
• D. Packet mode and session mode

Answer: (A)

IPsec secures communications by choosing how much of the original packet to protect. In Tunnel mode, the entire original IP packet is wrapped inside a new IP header, so the original header and payload are protected; this is used for gateway-to-gateway or network-to-network connections. In Transport mode, only the payload (and optional transport-layer data) is encrypted or authenticated, while the original IP header remains, which is used for end-to-end host-to-host protection. The option listing Tunnel mode and Transport mode directly reflects the two modes IPsec supports, making it the correct choice. Other terms like data link mode and network mode, or user mode and kernel mode, or packet mode and session mode are not recognized IPsec modes.

IPsec secures communications by choosing how much of the original packet to protect. In Tunnel mode, the entire original IP packet is wrapped inside a new IP header, so the original header and payload are protected; this is used for gateway-to-gateway or network-to-network connections. In Transport mode, only the payload (and optional transport-layer data) is encrypted or authenticated, while the original IP header remains, which is used for end-to-end host-to-host protection. The option listing Tunnel mode and Transport mode directly reflects the two modes IPsec supports, making it the correct choice. Other terms like data link mode and network mode, or user mode and kernel mode, or packet mode and session mode are not recognized IPsec modes.