Hello everyone. So in this
video we are going to discuss about DNS.
DNS is the protocol which works on port number
53.
DNS stands for domain name server. Sometimes also
called as domain name service or domain name
system.
So what is the use of DNS?
DNS has made our life more easier
and simpler.
Why because humans cannot remember
IP addresses humans tend
to remember names it is
easy for us to remember names.
machines can remember numbers and
IP addresses
So if I ask you to tell
me 10 shopping websites name, you will be able
to quickly tell me but you won't be able to
tell me the IP addresses of those website. Why because
you cannot remember numbers.
Perfect. So in this case DNS comes
to help
whenever we type any URL in the browser.
in the background the URL to IP
conversion
Is done by DNS?
The DNS server finds where to
locate the URL address or the
web address. The user has given
it it basically sees whether this
URL is pointing to
which IP address and then resolves it
and gives you the result onto your browser.
So DNS is used to URL to
IP mapping and vice versa.
You can also open a website by typing
the IP address.
or the URL
As you can see I've given an example of google.com. If
you type google.com into the
browser your request goes to this IP addresses.
This is done by DNS.
And vice versa. If you give the IP address your request
is going to resolve to google.com.
So, let's see the practical.
Over here on my terminal I am going to send a
ping request to Google.
So what is Ping so ping is
basically a command.
Or a utility which is used to send
an icmp request to the
server and no the status that
if the host is alive or down.
So basically ping is used to send
icmp request and get a reply for that
icmp request to determine the status
of the host.
So you can see I am sending a ping request to
Google and I'm getting a reply from Google.
As you can see, this is the IP address which from
which I'm getting the reply.
I will just copy this IP address.
And now I will open up a browser.
So as you can see in the browser, I'm going to paste this
IP address and I'm going to hit enter.
And let's see what happens.
Yes, so as you can see.
I am able to open Google using the IP
address as well as the URL. Let me
again give the IP address and hit enter. It redirects
me to the google.com.
To using the IP address as well as
the domain name. I am able to reach to this
web server. This is how a DNS works.
I hope you guys understood. Thank you.