Draytek Vigor2200 User Manual page 107

VPN
Mutual Authentication (PAP): Enable this only if the
connecting router requires mutual authentication. By default,
the option is set to No.
IP Address Assignment for Dial-In Users
Start IP Address: Enter a start IP address to be assigned to
the dial-in PPP connection. You should choose an IP address
from the local private network. For example, if the local
private network is 192.168.1.0/255.255.255.0, you could
choose 192.168.1.200 to be the Start IP Address.
Click "OK"
3.2 Creating an Access Account for a Dial-in User
After activating the dial-in capability, you must create an
access account for each dial-in user. The router provides 10
access accounts for dial-in users.
> Advanced Setup > VPN Remote Dial-In User Setup
VPN-8