Configuring your router to use Dynamic DNS (DDNS) is not complicated, but before we dive into the process, you need to have a basic understanding of what Dynamic DNS is.
Dynamic DNS, Dynamic Domain Name System, or DDNS is a method to keep a domain name synced to a changing IP address, as most computers and home routers don’t use static IP addresses. In other words is a network technology that allows to always keep your public IP address updated at all times to a domain name (e.g., something.com, mydomain.net, etc). (Also, check the complete definition at Wikipedia.)
The questions now is: Why would you want to configure Dynamic DNS into your router? There are various applications where this applies. For example, you have a FTP server or a small personal website running at your home and you need to connect from a remote location.
Having Dynamic DNS configured on your router will make it much easier to remember the address (e.g., friendly-address.com instead of 220.127.116.11), when configuring a connection or loading the web page, and you don’t have to manually keep track every time your public IP address changes.
In the next example, and the one I think could be very useful, would be when you need to connect to your home VPN to connect remotely to your computer or retrieved an important file you need to work on.
Now that you have the What and the Why, we’ll dive into the process to configure DDNS on a router, which is a really straight forward process.
By default (1) DDNS Service will be Disable, click on the drop-down menu and select the service of your choice — for this example we are choosing DynDNS.org. Leave the Do not use external ip check set to No. Then (2) just enter your username and password for your DynDNS.org account, and also (3) enter the Host Name you have created on DynDNS.org, e.g., thename.dyndns.org.
The last thing left to do is to scroll down the page, click Apply Settings and then Save. Then log in to your DD-WRT router and from the Setup tab, navigate to the DDNS section. You will then be redirected to the Dynamic DNS configuration page of the router.
You can refresh the page a see the DDNS Status to see that everything is working OK, or you can visit the page whatismyip.com, write down your public IP address, then from Windows you can start the command prompt and type: ping yourdomainname.service.com, and you should see successful replies from your public IP address.