Draytek Vigor3910 Series User Manual page 213

Item
IPSec Security Method
After finishing all the settings here, please click OK to save the configuration.
Vigor3910 Series User's Guide
Description
has been set in VPN and Remote Access >> IPSec Peer
Identity.
When the remote node is specified, all fields in this section are
required for IPsec Tunnels and L2TP connections with IPsec
Policy. Select any combination of Medium, DES, 3DES and AES
security methods as desired.
Medium (AH, Authentication Header) - Data will be
authenticated, but not be encrypted. By default, this option is
enabled. You can uncheck it to disable it.
High (ESP, Encapsulating Security Payload) - Payload (data)
will be encrypted and authenticated. You may select
encryption algorithm from Data Encryption Standard (DES),
Triple DES (3DES), and AES.
Local ID - Specify a local ID to be used for Dial-in setting in the
LAN-to-LAN Profile setup. This item is optional and can be
used only in IKE aggressive mode.
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