Dynamic DNS Servers

Sometimes you will get blocked when you try to access remote systems using the IP address itself. May be sometimes you are to check your local web server is running, that you setup in your home and having a dynamic IP address, when you asked your friend to check your server is running properly, and he/she types the url like http://117.193.123.113/mysite/index.php, sometimes he will get blocked from accessing your server, even if you enabled NAT and all done properly.

It is always easy to remember a site name than IP address and also the IP address, if you are having a dynamic IP will change each time (not always) when you reset the modem based on availability of IP addresses. In such cases there are services that provide you the facility of dynamic DNS servers, where you can create your domain, i.e. a sub domain of the service provider's top level domain. You can set the sub domain to point to the IP address you have. You need to update the ip corresponding to the domain each time if it changed (usually if the modem resets).

Suppose the above case, you are having the ip 117.193.123.113 and you want to test your home ftp server then you can create a domain like myhomeftp.dyndns.com and you can set that point to your home PC that is assigned an ip 117.193.123.113 (set up NAT to share the same public ip between modem and PC, so that the service running on your PC will be available to the public).

There are many such providers offering you the dynamic DNS, and i used the same service from dyndns.com for test purpose and also for the company i worked for, to use the ftp server i setup for the company, that I explained in previous article, as it is a static ip no need to update the dns server frequently.

They provides a number of choices for you to select the top level domain, like dyndns.com or homeftp.net etc.