## computer network - Class A Subnetting

### Class A Subnetting:

** **As we know the Class A network address has 24 bits available for host addressing. This means we can use up to 22 bits for subnetting.

The process of subnetting a Class A network is pretty much the same as it is for a Class B.

`Letâ€™s start:`

` Example as follows`

` 10.0.0.0 = Network Address`

` 255.128.0.0 = Subnet Mask`

` (11111111.10000000.00000000.00000000)`

Now we are applying top 5 formulas to find out subnets, hosts, valid subnets, broadcast address.

- How many subnets?

* Formula is:* 2

^{x}= number of subnets.

*x*is the number of masked bits, or the 1s. Because 128 is 1 bit on (10000000), the answer is 2

^{1}=2

- How many hosts per subnet?

* Formula is:* 2

^{Y}-2 = number of hosts per subnet. y is the number of unmasked bits, or the 0.

We have 23 host bits off (10000000.00000000.00000000), so the equation is 2^{23}-2 = 83,88,606 hosts (83,88,608-2).

- What are the valid subnets?

* Formula is:* 256-subnet mask = block size, or increment number.

So, 256-128=128. Remember, we'll start at zero and count in our block size, so our subnets are 0, 128.

** Like wise you can make subnetting of all class A IP addresses. **