2 – What is IPv4 Addressing 

IP Addressing (Internet Protocol Address) is a unique number given to a node on a computer network. It is of two types, i.e. IPv4 and IPv6.

Starting with IPv4.

It is a 32bit number give to a node on a computer network to communicate, sharing files and services.

It consist of 32bit numbers divided into 4 octets(blocks) of 8 bits each.

Each 32 bit binary digit can either be in an ON state or an OFF state i.e. 1 or 0.

Example

11000000.10101000.00000000.000000001 = 32 bits

(this is how the computer understands the IP Address )

Furthermore, this can be easily understood by we humans in decimal form.

Example

192.168.0.1

Please note this magic numbers : 128 64 32 16 8 4 2 1 in addition make up 255

Each octet represents an instance of the magic numbers.

So;

In here, for the first octet

128 + 64 = 192

128 + 32 + 8 = 168

No on bits = 0

1 = 1

This gives us 192.168.0.1 decimal which is equivalent to 11000000.10101000.00000000.000000001 in binary bits

Now that we are aware of and IP Address being divided into 4 Octets. It is further divided into 2 numbers

Namely Network ID and  Host ID

The Network Id represents the identity of the network whiles Host ID represents the identity of the computer or node on that network

Subnet Masks

A subnet mask is  used to determine the Network ID and Host ID portion  of an IPv4 address. Continue to understand better.