Hi Renoir,

I just thought I would add to what Walter stated on NAT. NAT is not specific to Windows but it is builtin to some versions of Windows. In fact, CISCO developed it. NAT is available on almost all operating systems as well as many routers and firewalls. In the corporate world, NAT is more commonly implemented via a router or firewall and not software on a server or workstation for performance reasons.

NAT or network address translation allows a single device to act as an agent between the internet and a local or private network. With NAT, only a single unique ip address is required to represent an entire group of workstations. There are two basic types:

Static NAT: the mapping of one unregistered ip address to a registered ip address (one-to-one). In other words, it would allow a workstation with a private ip address of 192.168.1.1 to be seen on the internet as 213.24.62.1.

Dynamic NAT: the mapping of an unregistered ip address to a registered ip address using a group of registered ip addresses. The computer with the ip address will translate to the first available public ip address in the range specified.

Most often, NAT is used to share internet connections so only one ip address has to be purchased.