QUESTION 6 Which of the following is a class A IPv4 address? a. 118.20.210.254 b. 183.16.17.30 c. 215.16.17.30 d. 255.255.0.0

a. 118.20.210.254

Explanation:

Here are the few characteristics of Class A:

First bit of the first octet of class A is 0.

This class has 8 bits for network and 24 bits for hosts.

The default sub-net mask for class A IP address is 255.0.0.0

Lets see if the first bit of first octet of 118.20.210.254 address is 0.

118 in binary (8 bits) can be represented as : 1110110

To complete 8 bits add a 0 to the left.

01110110

First bit of the first octet of class A is 0 So this is class A address.

For option b the first octet is : 183 in the form of bits = 10110111 So it is not class A address

For option c the first octet is 215 in the form of bits = 11010111 So it is not class A address

For option d the first octet is 255 in the form of bits = 11111111. The first bit of first octet is not 0 so it is also not class A address.