Question

You are given class C IP address 192.148.10.51 accompanied by a custom subnet mask of 255.255.255.240 Find the following by showing working with explanation:

i) How many subnets can be created?

ii) How many hosts in each subnet can be created?

iii) Write the range of useable IP Addresses in the first subnet.

iv) Write the range of useable IP Addresses in the last subnet.

Answer 1

The given IP address is:

192.148.10.51

The above address belongs to class C.

First octet range of class C: 192 to 223

The first three bits of the first octet of class C is used to identify the class and always set to 110.

The netmask of class C= 255.255.255.0

The netmask and subnet mask is used to divide the IP address as given below:

The netmask is a sequence of '1' followed by a sequence of '0' and it is used to divide an IP address into multiple subnets.

The subnet mask is a sequence of '1' followed by a sequence of '0' and it is used to separate a big network into smaller multiple networks.

The given subnet mask is = 255.255.255.240

The above subnet mask in binary representation is:

11111111 11111111 11111111 11110000

Here, four more bits are reserved for subnetting.

i)

The total number of subnets that can be created = 2⁴ = 16

ii)

The total number of host in each of the subnet is = 2⁴ - 2 = 14

Because the first address and the last address is used for the special purpose.

iii)

The first usable IP address in the first subnet is = 192.148.10.1

The last usable IP address in the first subnet is = 192.148.10.14

iv)

The first usable IP address in the last subnet is = 192.148.10.241

The last usable IP address in the last subnet is = 192.148.10.254