Subnetting is the process of dividing a single network into multiple small networks.
Converting host bits into network bits i.e. converting 0s into 1s
Subnetting helps in minimizing the wastage of IP address.
For Example :--
Engineering has = 40 hosts
HR has = 20 hosts
Sales has = 20 hosts
Technical Support has = 20 hosts
Executive Management has = 15 hosts
So in the above scenario we need,
40 IP for engineering department,
20 IP for HR department,
20 IP for Sales department,
20 IP for Technical support,
15 IP for Executive Management
Which means that we will be using class C IP for all
40 IP for engineering department 192.168.1.X
20 IP for HR department 192.168.2.X
20 IP for Sales department 192.168.3.X
20 IP for Technical support 192.168.4.X
15 IP for Executive Management 192.168.5.X
Class C has 256 IP but we are using only few IP address and rest IP are wasted. So to minimize this wastage we do subnetting.
Types of Subnetting:-
a) Fixed length subnet Mask.
b) Equal parts division
a) Variable length subnet Mask.
b) Non-equal parts division