Network Address Translation Basics 

Definition: I have one address I would like to share with everyone.

IP addresses have become hardly until the full adoption of IPv6 and expensive. So some smart people came up with network address translation (NAT), which enables a network that does not follow the internet’s addressing scheme to communicate over the internet. Private IP addresses have been reserved for internal LAN address use. These addresses can be used within the boundaries of a company, but they cannot be used on the internet. NAT enables a company to use these private addresses and still be able to communicate transparently with the computer on the internet.

Private IP address ranges

10.0.0.0—10.255.255.255                Class A networks

172.16.0.0—172.31.255.255             Class B networks

192.168.0.0—192.168.255.255        Class C networks

Many firewall vendors have implemented NAT into their products, and it has been found that NAT actually provides a great security benefit. When attackers want to hack a network, they first do what they can to learn all about the network and its topology, services, and addresses. Attackers cannot easily find out a company’s address scheme and its topology when NAT is in place, because NAT act as security guard by standing in front of the network and hiding the true IP scheme.