A.the outer label used to determine the next hop
B.the IPv4 label for the destination network
C.the IPv4 label for the forwarding router
D.the IPv4 label for the destination router

A.If the VPN server is configured for Xauth， the VPN client waits for a username / password challenge.
B.The Cisco Easy VPN feature only supports transform sets that provide authentication and encryption.
C.The VPN client initiates aggressive mode （AM） if a pre-shared key is used for authentication during the IKE phase 1 process.
D.The VPN client verifies a server username/password challenge by using a AAA authentication server that supports TACACS+ or RADIUS.
E.The VPN server can only be enabled on Cisco PIX Firewalls and Cisco VPN 3000 series concentrators.
F.When connecting with a VPN client，the VPN server must be configured for ISAKMP group 1，2 or 5.