An Internet address (IP address) is a unique 32-bit binary number given to a host and used for all interaction with the host. Each packet transmit across an Internet contains the 32-bit IP address of the sender (source) as well as the receiver (destination).

THE IP ADDRESS HIERARCHY:

Each 32-bit Internet address is divided into two parts:

• PREFIX:

 It shows the physical network to which the computers are attached.

• SUFFIX:

 It shows an individual computer on the network.

The physical network in an Internet is given a unique value called as a network number. No two networks can be given the same network number and no two computers on the same network can be given the similar suffix. A suffix number can be used on more than one network.

The IP address architecture guarantees two important rules:

1. Each computer is given a unique address.

2. Although IP address assignment must be coordinated globally, suffixes may be given locally.