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dns

i want to make dns tutorial using open office presentation.
And maybe a webpage. below here are notes.

dns 101

We all know that every computer on the Internet has an IP address

when you type in www.google.com how does the internet know what IP address to give you?

When you enter a website into firefox
it asks the dns servers it is assigned.

those dns servers find out the number that go with the name

the dns servers then send the ip address back to your browser so that it knows what computer to connect to.

Where does the DNS server get the numbers from?

there are two main ways dns servers find the ip addres to return for a particular name

1. they already knew it.

2. they asked another DNS server what it was

Every domain on the internet has a group of DNS servers that are incharge of its records. these servers are known as being authoritative.

if your DNS server doesnt already know what number to use it will find one of the Authoritative DNS servers for that particular domain.

your dns server will then know what ip address matches the name you requested.

But how does my dns server find out which DNS server is authoritative for a particular domain?

it asks the top level domain servers. so very important that most people forget they exist. but lets list some of the more popular ones net,org,edu,biz,info ahh and of corse the most popular of all COM

EVERYONE STOP
imagine what your life would be like if you never hear the spoken phrase "DOT COM"

every top level domain has a group of dns servers that hold NS records for all of the domains underneath it. the NS records contain the ip addresses of all the DNS servers that answer authoritatively for public IP addresses on the Internet.

and the most imporant of all

. our good old friend DOT

but not the one next to WWW or before COM

the one at the very end that noone even bothers typing because its always there

im talking about www.google.com. <---- that last DOT right there

that is the root servers. and every dns server on the internet already knows how to get to the root servers,

the root servers then where all the Top level domain servers are.
The top level domain name servers which know the ip addresses for the authoritative dns servers for all the registered domains. The authoritative name then tells us the ip address for WWW, FTP, where to send emails and maybe even sub domains, it can go on forever.