Subnetting

Subnetting :

Scenario:
Given IP 192.168.2.0
Default subnet Mask class c is 255.255.255.0

The above IP subnet mask allows only one network

you need more than that ,lets say 30

so try the subnet mask 255.255.255.248

or in Binary
11111111 11111111 11111111 11111000


5 1's in left most so it is 2*5 32 Networks.
3 zeros so 8 hosts or 6 to be accurate per network

so subnetting or VLSM is varying the subnet mask
to have the number of networks and hosts that
is required