Draytek Vigor2500V Manual page 41

For NAT Usage: (Default: Always Enable)
1st IP Address: Private IP address for connecting to a local private
network (Default: 192.168.1.1).
1st Subnet Mask: Subnet mask for the local private network (Default:
255.255.255.0/ 24).
For IP Routing Usage: (Default: Disable)
Enable: Enable the 2nd IP address settings.
Disable: Disable the 2nd IP address settings.
2nd IP Address: Set a public IP address.
2nd Subnet Mask: Set a subnet mask for the public IP address.
2nd Subnet DHCP Server: The following picture is for 2nd subnet DHCP
Server of the Vigor Router.
LAN TCP/IP and DHCP
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