Network address translation

From Sysadmin

Network address translation more commonly known as NAT is available in many different forms.

When not further qualified NAT normally prefers to many-to-one NAT and this is how the term is used for the remainder of this article.

Security

It is often argued that the use of NAT offers a security advantage. This isn't actually so - what offers the security advantage is the use of private RFC1918 address space since this prevents direct unsolicited connections from the Internet. NAT is often used to facilitate access from the private address space to the Internet. The key here is that the NAT and use of private address space are distinct and can occur separately.

Users of private address space could use application level proxies to provide access without using NAT. This was a common approach before NAT became widely deployed in the mid 90s.

It is even possible to use NAT without using private address space, although this is rare it is not unknown.

This page is a stub. Robert will add additional information to the page later.