NAT

NAT:-

       IT stands for network address translation.

            The current implementation of IPaddressing provides user with a very limited number of IP addresses that can be used for connectivity purpose. To solve this problem a number of organization have started implementing NAT addressing ,which allows them to use a single public IP address for a large number of internal system having unique private IP addresses.  All internal system in such a Nat network use a common public IP address to communicate with all external system on the Internet. 

                Let us Assume that there are a internal system ’ x’ (Many system connected with each other) having private IP address is unique. They all are connected with NAT, Which have a public IP address and NAT are Connected through the INTERNET.

      When any of private IP address of computer send data It send to only on NAT. Then NAT change the IP address of that packet then send to the Inertnet.(Change internal IP address to public IP) .The NAT use  Index table for Identifie  internal system because when reply comes from the Internet then it send the packet to internal system. IT works on two network junction.