SMC Networks Barricade SMC7004VWBR V.2 - Manual (Page 65)

Advanced Setup
61
DDNS (Dynamic DNS) Settings
Domain Name is a series of alphanumeric strings separated by
periods, that is the address of a network connection and that
identifies the owner of the address.
Dynamic DNS provides users on the Internet with a method to tie
their domain name(s) to computers or servers. DDNS allows your
domain name to follow your IP address automatically by having
your DNS records changed when your IP address changes.
The Server Configuration section automatically opens the port
options checked in the Virtual Server section. Simply enter in the
IP Address of your server, such as a web server, and then click
on the port option HTTP Port 80 so users can access your server
from the WAN connection (Internet).