What feature of IPSec ensures data integrity during transmission?

What feature of IPSec ensures data integrity during transmission?

• Anti-replay
• Non-repudiation
• Encryption
• Authentication 

EXPLANATION

Internet Protocol Security (IPSec)

Cisco IOS uses the industry-standard IPSec protocol suite to enable advanced VPN features. The PIX IPSec implementation is based on the Cisco IOS IPSec that runs in Cisco routers.
IPSec acts at the network layer, protecting and authenticating IP packets between a PIX Firewall and other participating IPSec devices (peers), such as other PIX Firewalls, Cisco routers, the Cisco Secure VPN Client, the VPN 3000 Concentrator series, and other IPSec-compliant products.
IPSec enables the following Cisco IOS VPN features:

• Data confidentiality—The IPSec sender can encrypt packets before transmitting them across a network.
• Data integrity—The IPSec receiver can authenticate packets sent by the IPSec sender to ensure that the data has not been altered during transmission.
• Data origin authentication—The IPSec receiver can authenticate the source of the IPSec packets sent. This service is dependent upon the data integrity service.
• Antireplay—The IPSec receiver can detect and reject replayed packets.