What is NAT?

NAT or Network Address Translation

When the internet was initially created, there was no real shortage of IP addresses. However as internet usage increases an acute shoratge of IP addresses was seen world wide. This lead to the emergence of NAT.

Advantages of NAT.

1: Reduces need for IP addresses 

2: Improve security basis implementation of networks.

                                                                                               

.For example let us assume that there are 100 employees in an office. Every employee has a phone extension number. There is a receptionist in the office that controls all incoming and outgoing phone calls in the office. Let us call her NAT. Receptionist has a list of employees names and their respective extension numbers. Now let see how incoming  and outgoing calls are handled.

Out going calls: Employee calls the receptionist and then calls the destination number. The person at the destination number will only see the main office line phone number and not the employees inside desk number. This give the employees security and prevents annoying people from calling them. It also allows the office to use one single main office phone number to large number of employees. Hence, reducing the total number of telephone numbers are needed.

A NAT system operates in the same way. All the employees in the office are given a unique internal IP addresses which normally cannot be accessed from outside the network. When a system wants to connect to the internet, then the router assigns the system a public IP addresses that has been bought by the company. The internal IP address of the employees remains protected.