D-Link DSL-2740R User Manual page 44

Section 3 – Configuration
in the form hostname.dyndns.org, Many ISPs assign public IP addresses using DHCP, this can make it difficult to locate a specific host on the LAN
using standard DNS. If for example you are running a public web server or VPN server on your LAN, this ensures that the host can be located from
the Internet if the public IP address changes. DDNS requires that an account be setup with one of the supported DDNS providers.
Tick the Enable Dynamic DNS check box, enter the required DDNS information, click the Apply Settings button, and then click the Reboot button
on the left panel to let your changes take effect to set this information in the Router.
DDNS requires that an account be setup with one of the supported DDNS servers prior to engaging it on the Router. This function will not work without an accepted
account with a DDNS server.
Note
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