Question

As the network administrator for a growing ISP, you want to make efficient use of your network addresses. One of the networks addresses IANA assigned to you is a Class C network of 192.168.88.0. You have decided to use the addresses in this Class C network to satisfy the IP address requirements of 18 corporate customers who need between 20 and 24 addresses each. calculate a subnet mask that meets their needs. List the subnet mask and the first four subnetwork addresses the mask will create.

Its very urgent i need it in few minutes

Answer 1

In Class C Network say, Given we have IP address: 192.168.88.0 using this we can create 254 hosts ( 192.168.88.0 to 192.168.88.254 ) due to fact that 192.168.88.0 to 192.168.88.255 is the network addresses).

In Class C Network say, the subnet mask looks like 255.255.255.0 and if we breakdown the decimal into binary its representation is as follows: ( 11111111. 11111111. 11111111. 00000000 )  

According to given conditions, if we need to fulfill 18 corporate customers the subnet mask will end up being like this :

11111111. 11111111. 11111111. 1|1|1|1|0|0|1|0 in binary representation.

In order to calculate in decimal number it would be : 128 + 64 + 32 + 16 + 2 = 242 that's the subnet mask according to the requirement is 255.255.255.242.

End up with 18 networks with 18 addresses per network.

The first four network adddresses would be as follows:

Network-1 : 192.168.88.0

Network-2 : 192.168.88.18

Network-3 : 192.168.88.36

Network-4 : 192.168.88.54