4-1
4WirelessWirelessWireless Router
4
Advanced Configuration
This section covers advanced configuration of the Wireless Router. These functions
include:
•
Configuring and Using Port Address Translation
•
Static DHCP Assignments
•
Creating Virtual Private Networking Connections
•
Using Packet Filtering
•
Configuring IP Settings
•
Configuring IPX Settings
•
Configuring Bridging Settings
Configuring and Using Port Address Translation
The Port Address Translation (PAT) feature of Wireless Router is a powerful and
economical way of allowing Internet access to public machines on your LAN without
applying for or configuring public IP addresses. It complements single IP address
translation so that not only does it give users the benefits and administrative
simplicity of a using a single IP address ISP account, it also provides the flexibility of
a configurable combination of secure, privately addressed workstations and port
mapped publicly accessible applications.
You have already read about private addressing on your LAN in Chapter 1. PAT
extends this concept to provide a way to specify the applications on LAN which you
want Internet users to be able to access. This is done by configuring the router to re-
route an Internet packet that Wireless Router receives from the Internet into the TCP
or UDP port that the application uses on the privately addressed LAN machine that is
actually running that application. In this manner, a privately addressed PC on your
LAN that is running a Web Server, for example, may be accessed from the Internet by
configuring the Wireless Router to translate all packets addressed to its public address
containing the destination port 80 (the standard HTTP port), to a privately addressed
NT Server, perhaps, which is running a Web Server application. The remote Internet
user never knows about, nor can access, any other services running on the actual PC
with which he or she is communicating.
In this way a PC application is “mapped” to a port on the Wireless Router.
Note:
When port 80 (HTTP) and/or port 23 (telnet) is mapped to a private IP
address, special consideration must given for remote administration of the Wireless
Router since those are the ports which are normally used for the browser-based
ARM
interface , respectively.When port 80 is re-mapped, remote administrators must re-
map port 80 on the router to another port. Thus, the remote administrator may then
invoke
ARM
using the re-mapped port. Note that, using the extended URL format, if
ARM
were re-mapped to port 8080, the URL for accessing this location is
http://
192.168.168.230:8080
.When port 23 is re-mapped, remote administrators must re-
