Netopia R7200 manual HOW NAT Works

10-2 User’s Reference Guide

NAT works by remapping the source IP address of traffic from the LAN to a single static or dynamically assigned IP address shown to the remote side of the router.

HOW NAT WORKS

With NAT

192.168.1.100

ISP* 192.168.1.102 192.168.1.103

163.167.132.1

192.168.1.104

192.168.1.105

192.168.1.106

Without NAT
	163.167.132.1
163.167.132.1	163.167.132.2
	163.167.132.3
163.167.132.2
163.167.132.3
163.167.132.4
163.167.132.5	163.167.132.4
163.167.132.6
	163.167.132.5
	163.167.132.6
*or corporate intranet router

The feature can be implemented on a per–connection profile basis. The network router can use two or more connection profiles simultaneously to connect to two or more networks. Each profile can have NAT enabled.

When NAT is enabled, the Netopia R7200 can use either a statically assigned IP address or one dynamically assigned each time the router connects to the ISP. While a dynamically assigned IP address offers the ISP more flexibility, it does have an important limitation: the router requires a static IP address to support Web, FTP, or other services available to the WAN. To support these services with NAT enabled, a service can be associated with only one machine on the LAN.

When connected to the Internet or some other large network using NAT, the individual machines on your LAN are not directly accessible from the WAN. NAT provides an inherently secure method of connection to the outside world.