Answer to Question #326475 in Computer Networks for VIk

Question

Consider a scenario where a “Class A” network is divided into 3 subnets of fixed length. Design each subnet and find the IP Range and subnet mask of each subnet. (Choose any Class A address).

Answer 1

Choose Class A network 17.0.0.0/8.

To have 3 subnets we should reserve 2 bits ($2^S\ge number\ of\ subnets$, where $S$ is number of bits).

Subnet 1:

17.64.0.0/10

In binary form: $\underbrace{00010001}_{\text{Network}}.\underbrace{01}_{\text{Subnet}}\underbrace{000000.00000000.00000000}_{\text{Address}}$ .

IP Address range: 17.64.0.1 - 17.127.255.254

(00010001.01000000.00000000.00000001 - 00010001.01111111.11111111.11111110)

Subnet mask: 0.63.255.255

(00000000.00111111.11111111.11111111).

Subnet 2:

17.128.0.0/10

In binary form: $\underbrace{00010001}_{\text{Network}}.\underbrace{10}_{\text{Subnet}}\underbrace{000000.00000000.00000000}_{\text{Address}}$ .

IP Address range: 17.128.0.1 - 17.191.255.254

(00010001.10000000.00000000.00000001 - 00010001.10111111.11111111.11111110)

Subnet mask: 0.63.255.255

(00000000.00111111.11111111.11111111).

Subnet 3:

17.192.0.0/10

In binary form: $\underbrace{00010001}_{\text{Network}}.\underbrace{11}_{\text{Subnet}}\underbrace{000000.00000000.00000000}_{\text{Address}}$ .

IP Address range: 17.192.0.1 - 17.255.255.254

(00010001.11000000.00000000.00000001 - 00010001.11111111.11111111.11111110)

Subnet mask: 0.63.255.255

(00000000.00111111.11111111.11111111).