SUBNETTING

 FORMULA TO FIND THE BLOCK SIZE : 

Host: Represents no. of users in the network

To find no of users:  2^h-2  >= User Requirement 

To find Host Bit (h):  32 - CIDR value

Subnet: A logical subdivision of an IP network

To find subnets:  2^(CIDR Value - Bit value of the given class)

Subnet bit/CIDR value: Classless Inter-Domain Routing - Current number of network bits

To find CIDR Value(subnet bit): Total value of octet i.e. 32 - Host bit value

Subnet Mask: It is used to differentiate host bit and network bits in an ip address

by CIDR value 

Network bits are represented as  1 and Host bits are represented as 0.

To find Subnet mask: Exclude the host bit value from the octet value from right to left and add the remaining bit values

Wildcard Mask: It is the reverse of subnet Mask

To find Wildcard mark: 255-SM

Network bits are represented as  0 and Host bits are represented as 1.