What is DDNS?

By | July 9, 2009

We all have heard about DNS(Domain name System).Let see what is DDNS

DDNS :  Dynamic Domain Name System.

It is the service that maps the Internet domain names to Ip address. It serves exactly the same purpose as the DNS with some addition. It allows anyone hosting a web or FTP server to advertise a public name to prospective user. A popular application of DDNS is to provide a residential user’s Internet gateway that has a variable, often changing, IP address with a well known hostname resolvable by network applications through standard DNS queries.

DNS only works with static IP address, however DDNS is designed to work with Dynamic IP address, such as the IP address assigned by the DHCP server. This makes DDNS a good service which is good for the home networks, which often reciev dynamic public IP address from the ISP(Internet service provider) that occasionaly change.


Using DDNS is very simple. A user can sign up with the DDNS provider and install network software on HOST to monitor the IP address. Dynamic DNS providers provide a client program software that automates the discovery and registration of client’s public IP addresses. This client program is executed on a device on the network(private).It connects to the service provider’s systems and causes those systems to link the discovered public IP address of the home network with a hostname in the DNS(Domain Name System). Now, depending upon the provider the hostname is registered within the domain by the provider or to the customers domain.

For example, dyndns.com provides a free dynamic DDNS service via software that can run on Windows, Mac or Linux computers.

DDNS has a disadvantage that it needs an additional host software.