ZyXEL Communications MAX-206M1R User Manual

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Chapter 8 The NAT Configuration Screens
User’s Guide
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The following table describes the labels in this screen.
8.3  Port Forwarding 
A NAT server set is a list of inside (behind NAT on the LAN) servers, for example, 
web or FTP, that you can make accessible to the outside world even though NAT 
makes your whole inside network appear as a single machine to the outside world.
Use the ADVANCED > NAT Configuration > Port Forwarding screen to 
forward incoming service requests to the server(s) on your local network. You 
may enter a single port number or a range of port numbers to be forwarded, and 
the local IP address of the desired server. The port number identifies a service; for 
example, web service is on port 80 and FTP on port 21. In some cases, such as for 
unknown services or where one server can support more than one service (for 
example both FTP and web service), it might be better to specify a range of port 
numbers. 
In addition to the servers for specified services, NAT supports a default server. A 
service request that does not have a server explicitly designated for it is 
forwarded to the default server. If the default is not defined, the service request is 
simply discarded.
Table 25   ADVANCED > NAT Configuration > General
LABEL
DESCRIPTION
Enable Network 
Address Translation
Select this if you want to use port forwarding, trigger ports, or any 
of the ALG.
Max NAT/Firewall 
Session Per User
When computers use peer to peer applications, such as file 
sharing applications, they may use a large number of NAT 
sessions.
 If you do not limit the number of NAT sessions a single 
client can establish, this can result in all of the available NAT 
sessions being used. In this case, no additional NAT sessions can 
be established, and users may not be able to access the Internet. 
Each NAT session establishes a corresponding firewall session. Use 
this field to limit the number of NAT/firewall sessions each client 
computer can establish through the WiMAX Modem. 
If your network has a small number of clients using peer to peer 
applications, you can raise this number to ensure that their 
performance is not degraded by the number of NAT sessions they 
can establish. If your network has a large number of users using 
peer to peer applications, you can lower this number to ensure no 
single client is using all of the available NAT sessions. 
Apply
Click to save your changes.
Cancel
Click to return to the previous screen without saving your 
changes.