Domains and DNS

Most of us already be knowing the use of DNS, i.e. for resolving names to IP address

on which all kind of network is based. Here this article explains the basics of DNS

and then takes you further to understand the internet and web hosting.

DNS : Used to resolve names into IP address.

Now let’s see how it works

Every computer connected to internet has these IP Addresses assigned.

IP Address for the machine

Gateway IP Address

DNS Server IP Address.

Now our main target is the last one, i.e. DNS

Whenever our machine wants to resolve any name, it contacts the DNS server (which

is provided by the ISP) for the name resolution i.e. IP address for the name.

For example. In the browser when you type www.example.com it will go to the DNS

for name resolution, after it is resolved the IP address is returned to the computer.

When the request comes to the DNS server, it will look into its own cache

(in the server itself) if it has any information about the domain name, if it doesn't have

any information it would start its journey by going to the Root Name Server

Root Name Server : Is again a DNS server that answers the request for the dns

names and redirects the request to the tld of the requested name.

tld stands for Top-Level-Domain, these are the .net, .com, .org, .in, etc

For example: If request comes for www.padipa.net, it looks for the last extension

Here which is .net, then redirects the request to .net DNS server.

Now the .net DNS server then redirects to the DNS server that are actually hosts

The zone for the requested domain.

For example : when the request comes to .net tld DNS server, it checks the domain name

Here which is padipa, then gives away the entry for the name server for that domain

The name server are the DNS server that host the zone file for the domain, i.e all the

information about the hosts in that domain.

For example : After the request comes to the specified name server, it looks into the

zone file for the host www (of the www.padipa.net) and provides the IP address of the

webserver hosting the website of www.padipa.net.

After the IP address is retrieved by the requesting computer it contacts the web server

asking for the web files and gets it.

Now coming to web hosting industries.

Lets start with as example,

Suppose you want host own domain say jumanji.com you want a web-site by

that name www.jumanji.com and your own mail domain i.e your own email address

myname@jumanji.com

Where do you start ?

There are two things involved to meet the above requirement,

1) Domain Registration

2) Hosting

Domain Registration : You have to register your domain with a domain registrar,

Domain registrars are companies that have links with the tld DNS server, once you

have registered your domain with the domain registrar's they would put your domain

record onto the tld DNS servers, so that your domain is available for Internet access.

Normally for the domain to reflect over the internet tld DNS server it takes max of

24 hours.

Hosting : You have to contact web hosting provider, they would host your DNS zone,

web server, mail server as to meet our specified requirements.

You will get a server that is accessible over internet, now the IP address of the server

that host the DNS zone is the name server for you, you would put this information in

Domain registration form which you have done in the 1st part.

Now the server which you got is to be configured with web server, mail server,

software. (which is normally provided by the web hosting provider)

Now once your web server is configured for your, you would be given FTP login

details so that you could upload your web-sites files onto to your web server.

Images speak thousand words, check the below image for more clarification.