Microsoft® Windows® 2000 Security Handbook

Network Address Translation (NAT)

Because each class of solution I've mentioned so far (with the exception of the host-based variety) includes NAT, let's dig in to get a technical understanding of what NAT actually does.

As mentioned earlier, NAT allows you to share one true Internet IP address among many internal computers. With NAT, I connect all five of my computers in my home to the Internet, using (and paying for) only one IP address from my broadband provider.

Also, NAT increases security dramatically by hiding your internal machines. In fact, under most circumstances, the only machine that is addressable from the outside world is the machine or device implementing NAT.

Note

NAT is defined in RFC 1631.

What NAT Does

Consider my home ...