Netopia 4541 - Manual (Page 110)

9-26 User’s Reference Guide
MultiNAT Configuration Example
To help you understand a typical MultiNAT configuration, this section describes an example of the type of
configuration you may want to implement on your site. The values shown are for example purposes only. Make
your own appropriate substitutions.
A typical DSL ser vice from an ISP might include five user addresses. Without PAT, you might be able to attach
only five IP hosts. Using simple 1-to-many PAT you can connect more than five devices, but use only one of your
addresses. Using multiNAT you can make full use of the address range. The example assumes the following
range of addresses offered by a typical ISP:
Public IP addresses assigned by the ISP are 206.1.1.1 through 206.1.1.6 (255.255.255.248 subnet mask).
Your internal devices have IP addresses of 192.168.1.1 through 192.168.1.254 (255.255.255.0 subnet
mask).
In this example you will statically map the first five public IP addresses (206.1.1.1 - 206.1.1.5) to the first five
corresponding private IP addresses (192.168.1.1 - 192.168.1.5). You will use these 1-to-1 mapped addresses
to give your ser vers “real” addresses. You will then map 206.1.1.6 to the remaining private IP addresses
(192.168.1.6 - 192.168.1.254) using PAT.
The configuration process is as follows:
From the Main Menu go to the Easy Setup and then the Connection Profile screen.
Local WAN IP address: 206.1.1.6
Local WAN subnet mask: 255.255.255.248
Remote IP address: 206.1.1.254
Default gateway: 206.1.1.254
Netopia Router's address is: 192.168.1.1
Web ser ver's address is: 192.168.1.253
Mail ser ver's address is: 192.168.1.254
FTP ser ver's address is: 192.168.1.253
Main
Menu
Easy
Setup
Connection
Profile