多项选择题
A.IKE keepalives are unidirectional and sent every ten seconds
B.IPsec uses the Encapsulating Security Protocol （ESP） or the Authentication Header （AH）protocol for exchanging keys
C.To establish IKE SA, main mode utilizes six packets while aggressive mode utilizes only threepackets
D.IKE uses the Diffie-Hellman algorithm to generate symmetrical keys to be used by IPsec peers
多项选择题 Study the exhibit carefully. The Cisco IOS IPsec High Availability （IPsec HA） Enhancementsfeature provides an infrastructure for reliable and secure networks to provide transparent availability of the VPN gateways - that is， Cisco IOS Software-based routers. What are the twooptions that are used to provide High Availability IPsec？（）
单项选择题 IPSec VPN is a widely-acknowledged solution for enterprise network. What are the four steps tosetup an IPsec VPN？（）
单项选择题 WhichstatementcorrectlydescribesIPsecVPNbackuptechnology？（）