CLASSFUL ADDRESSING networking notes

CLASSFUL ADDRESSING

Occupation of the address space

In classful addressing, the address space is divided into five classes:
                                             A, B, C, D, and E.

Example 6

How can we prove that we have 2,147,483,648 addresses in class A?

Solution

In class A, only 1 bit defines the class.

The remaining 31 bits are available

for the address. With 31 bits,

we can have 2³¹ or 2,147,483,648 addresses.

Example 7

Find the class of the address:            00000001  00001011   00001011 11101111

Solution

The first bit is 0. This is a class A address.

Example 8

Find the class of the address:               11000001  10000011   00011011 11111111

Solution

The first 2 bits are 1; the third bit is 0.

This is a class C address.