Draytek Vigor2760 series User Manual page 281

Available settings are explained as follows:
Item
Dial-In Settings
lifetime of key should be defined. The default value is
28800 seconds. You may specify a value in between
900 and 86400 seconds.

IKE phase 2 key lifetime-For security reason, the
lifetime of key should be defined. The default value is
3600 seconds. You may specify a value in between
600 and 86400 seconds.

Perfect Forward Secret (PFS)-The IKE Phase 1 key
will be reused to avoid the computation complexity in
phase 2. The default value is inactive this function.
Local ID-In Aggressive mode, Local ID is on behalf
of the IP address while identity authenticating with
remote VPN server. The length of the ID is limited to
47 characters.
Index(1-15) - Set the wireless LAN to work at certain time
interval only. You may choose up to 4 schedules out of the
15 schedules pre-defined in Applications >> Schedule
setup. The default setting of this field is blank and the
function will always work.
Description
Allowed Dial-In Type - Determine the dial-in connection
with different types.

PPTP - Allow the remote dial-in user to make a PPTP
VPN connection through the Internet. You should set
269 Vigor2760 Series User's Guide