Question

Give the mask in the dotted-decimal notation:

a. For a block of Class A which results in 32 subnets

b. Which combines 2048 Class C blocks into a supernet

c. For a block of Class B which results in 64 subnets

d. Which combines 16 Class B blocks into a supernet

Answer 1

An IP address is an identifier or label used to identify a machine on the internet or a particular network. Each of the devices on the internet must have an IP address for identification.

The netmask and subnet mask is used to divide the IP address.

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 subnet mask is used to separate the IP address into a network address and host address.

It is made by setting '1' to all network bits and '0' to all host bits. In a network, the first and last IP addresses are used for the special purpose and the remaining addresses are used as a host address.

Classful Addressing:

In classful addressing, an IP address is related to a class and we need to purchase a class of the IP addresses as per the requirement.

Address class:

Class A:

The range of the first octet: 0 to 127

Subnet mask = 255.0.0.0

Class B:

First octet range: 128 to 191

Subnet mask = 255.255.0.0

Class C:

First octet range: 192 to 223

Subnet mask = 255.255.255.0

a.

The netmask for a block of Class A which results in 32 subnets is given below:

255.248.0.0

b.

The netmask which combines 2048 Class C blocks into a supernet is given below:

255.248.0.0

c.

The netmask for a block of Class B which results in 64 subnets is given below:

255.255.252.0

d.

The netmask which combines 16 Class B blocks into a supernet is given below:

255.240.0.0