DHCP & DNS

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               What is DHCP and DNS ??

DHCP: Dynamic Host Control Protocol

It's a protocol used to assign IP addresses dynamically instead of assigning static ip's to each.
The process involves a process called DORA process.
D - Discover
O - Offer
R - Request
A - Acknowledgement

D - Discover:

 Host (PC, printer, laptop, Access systems..etc, IOT) sends a UDP broadcast to the server.

Packet from Host --> server

O - Offer:

The server offers a Unique IP address to the host in response to the Broadcast.

Packet from server --> Host

R - Request:

The host requests for the IP address offered by the server.

Packet from Host --> server

A - Acknowledgement:

The server sends a acknowledgement packet along with details of IP address, Subnet mask, gateway, Dns server1 and Dns server 2.


Packet from Server --> Host

DNS: Domain Name Server.

As we humans are uniquely identified by our names, Every website is uniquely accessed by it's domain and it's IP address.

For a machine, it won't understand the keywords (domain name, website address.. etc), it understands only it's IP address.

The Website you typed in your browser is accessed only through the IP address of the Domain.

For example : if you type google.com in your browser, this google.com is converted to 8.8.8.8
 By your DNS server.

DNS server makes this conversion. Without DNS server We can't access domains with their domain names.

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