What Is DNS Server

 

             

  

What is DNS

 

In this article we are going to talk about DNS service and the server configurations, in addition to IP addressing subnetting, domain description, and how this correlation works.

DNS “Domain Name Service” is a service that translates the domain names of the websites into IP addresses that the network equipment can understand. The Domain Names are easy to be remembered and has meaning to the humans, on the other hand the internet is based on unique IP addresses “Public IP Addresses”  

 

The communication process over the internet is performed on the basis of IP addresses and not on the domain names. A Domain name server service translates the domain name into its corresponding IP address for example the domain name www.abc.com might be translated to 102.222.34.48. The DNS system is actually perform its own check and do translation.

In case the Domain name server not able to translate a domain name, it looks for another one and so on until the exact IP address is returned. The DNS translating between the internet names and internet ip addresses.

 

How DNS Works

 

DNS arrange and organize the hostnames in the form of hierarchy. A domain is a group of the sites that are related to each other’s because they form a network (all computers that are geographically close as well. Universities and education centers are usually grouped under .edu domain with each university or college using a separate sub domain.

While the majority of the subject does not require that much technical knowledge, there is one important technical part of the Domain name server.

When you type a name like example.com in your internet browsers it finds a way to map that name to the internet IP numbers, by which the internet easily reach the example.com computer. For this goal your computer is using DNS of your Internet service provider company. All internet traffic working and depending on these numbers (IP addresses) and the important factor is that looking up for the name is done by Domain name server “DNS”.

 

That computer has a list of the host names/IP address mapping list, which is regularly updated by the root DNS. Root DNS servers are actually the master servers that can support you look up any name. All the root DNS servers make a copy of their data from the one master server, which is under the control of ICANN. The root servers usually include a list that can support you in looking for the top level domains like .com, .net, org and .info etc. The ISP sends the DNS request for the particular domain name to the root DNS sever and then the root server directs the request to the master server. By this, you can get the answer with your requested domain name.

 

IP routing and root servers

 

The domain lookups are exchanged  to and from the root servers because main routers on the internet, ISPs and backbones have the correct route to reach them in redundant way.

 

Domains Description

 

.edu: This domain name is used by the educational institutes and centers like colleges and universities

.com: This domain name is used by the commercial institutes/organizations and companies.

.Org: This domain is used by the non-commercial or community organizations.

.net: Administrative hosts, gateways and other networks.

.mil: This is used by the U.S. military institutions.

.Gov: This is used by the government institutes.

.info :Used by the Informative sites.

 

There is a common clarification which is how large is the internet and how Domain name server working and serving all these requests. Domain name server simply provides a mapping between hostnames and the IP addresses. When you dial in your ISP number and access it how does it get the answer in the form of requested domain name for you. It’s most likely that ISP may not have stored the information (requested site). In this case firstly the ISP server will send the request to the root-servers. These are the group of very high-powered and redundant servers that know all about the top level domains like .com, .org, .net, .info and all the country domains.

 

Summary

So, to summarize at the beginning the ISP’s name server communicate with the root-servers. If the root-servers is not able to handle the requested information then redirect the request to the GTLD servers for any type of top level domain and the answers return back to the ISP’s name servers with the requested information. At each step, ISP’s name server is caching all the information for any future request to the same name. The Domain name server is very important to the internet because without a domain name systems (DNS) its impossible to communication on the internet.