NAT

NAT is used in routers. The purpose of NAT is to translate a set of IP addresses, to another set of IP addresses. Currently there is a limited amount of IPv4 addresses in the world, and so in order to help preserve them, NAT was created alongside with private IP addresses

Types of IPv4 Addresses

   1. Public: publically registered on the internet and provided to us by our internet service providers (ISP). You MUST also have one in order to be able to acccess the internet

   2. Private: These are not publically registered, and they are assigned to us by our routers and so in turn you CANNOT directly access the internet. Private IP addresses are used, for example; In your homes, or businesses.

   3. Below is an example of NAT being used with routers

1. Lets say we have three devices inside our homes and when we want to use the internet with them, their private IP addresses (ie 10.0.3) will be translated by NAT in the router, to the public IP address which we can then use to access the internet.

Things to Note

• NAT translates Private to public
• NAT ALSO translates Public to private
• NAT enables us to be able to connect multiple devices using the same public IP, which in turn helps to be more effecient utilizing IPv4 (Remember in the very beginning we said there are only a limited amount of IPv4) in the world!