Operation Manual

Vigor2100V series
5-1
1
Chapter 5
NAT Setup
5.1 Introduction
NAT is a method of mapping one or more IP addresses and/or service ports
into different specified services, where NAT stands for Network Address
Translation. It allows the internal IP addresses of many computers on a
Local Area Network (LAN) to be translated to one public address, saving
users’ cost. It also plays a security role by obscuring the true IP addresses
of important machines from potential hackers on the Internet. For
convenience, we called a router having the NAT facility as a NAT-enabled
router.
Usually you will use your Vigor router as a NAT-enabled router. The
NAT-enabled router gets one globally re-routable IP address from the ISP and
assigns private network IP addresses defined by RFC-1918 to local hosts.
The NAT-enable router translates the private network IP addresses to such a
globally routable IP address so that local hosts can communicate with the
router and access the Internet.
5.2 NAT Setup
Click NAT Setup to open the setup page. On the page, you will see the
private IP address defined in RFC-1918. Usually we use the 192.168.1.0/24
subnet for the router. Also, as stated before, the NAT facility can map one or
more IP addresses and/or service ports into different specified services. In
other words, the NAT function can be achieved by using port mapping
method.