How is subnetting done?

Answer 1

Read the book Network+ by Todd Lammle. I still need to perfect it though...

or there is a three step process to do which dumbs it down into a super easy process that works.

1. Find the number of networks and convert into binary.

for example, you need 5 networks so in binary that is 00000101

2.Reserve the bits in the subnet mask then find the increment

for example if the binary number that you need is 00000101 then its 3 bits. then the 3 bits will be placed as 1's from the left to the right until there are no more bits to place. (note: if 255.255.255.0 = 11111111.11111111.11111111.11100000 will be the subnet converted into binary) the Increment will be the lowest network bit that you have, converted into a decimal number. (i.e. in 11100000, the lowest network bit is 32)

3.Use the increment to find your network ranges.

x.x.x.0-x.x.x.31

x.x.x.5-x.x.x.63

x.x.x.64-x.x.x.95

x.x.x.96-x.x.x.127

.....

.......

........and so on and so forth all the way up to x.x.x.254