What are Subnets

• Networks can be broken down further into what are called subnets.

• These, as their name implies, are just sub–networks that group together devices that can communicate with each other.

• You may have seen an IP address before written like 192.168.1.0/24

• This actually represents the address range for a /24 subnet.

• Let's break this down.

Subnetting Breakdown :

• An IP address is made up of 4 numbers that range from 0–255 and are separated by dots.

• These numbers are each called octets because they are ultimate made up of 8 bits.

• All together, an IP address contains 32 bits ( 8 × 4 = 32 ).

• When we are talking about a /24 network, it simply means that the first 24 bits ( or the first 3 octets ) are set in stone; this section of the address is known as the network address.

• So when we have a subnet like 192.168.1.0/24, the 192.168.1 part is going to be the same for every address on that subnet, with the only difference being the last octet ( the 0 ).

• As a result, a /24 subnet can only have 256 addresses, AKA, it can only have 256 hosts.