What are the functions of network address translation?

Network Address Translation (NAT) is a mechanism, through which one or more local IP addresses are translated into one or more global IP addresses. To access the local host also, the global IP addresses are converted to the local IP address.

Network Address Translation (NAT) Types

There are three ways to construct NAT. These are as follows −

  • Static NAT
  • Dynamic NAT
  • Port Address Translation (PAT)

Functions of NAT

The functions of NAT are explained below −

Address translation for data transfer

The border router is configured for NAT. The border router has two parts

  • Local interface
  • Global interface.

When the packets are transmitted from local host to another host in another network, then the packets are moved from local network to global network.

Then, the NAT process of the border router converts the local IP address of the transmitted packet to a global IP address.

When that packet moves from global network to local network, then again the global IP is converted to local IP and the packet reaches the local host of that network.

Security in IP addresses

NAT provides privacy of the device IP addresses by keeping them hidden when traffic flows through the network. Using the IP masquerading process NAT hides the device IP addresses.

Eliminates address renumbering

It eliminates the address renumbering, when a network evolves.

Firewall security

It has important applications in firewall security, by conserving the number of public addresses within an organization along with strict control over accessing resources at both sides of the firewall.

Advantages of NAT

  • Public IP address sharing.
  • Easier Explanation.
  • Greater local control.
  • Increase security.
  • Mostly Transparent.

Disadvantages of NAT

  • Complexity.
  • Problems due to lack of public address.
  • Compatibility with certain application.
  • Problems with security protocol.
  • Performance reduction.