ZyXEL 793H 사용자 가이드

 Chapter 7 Network Address Translation (NAT) Screens

P-793H User’s Guide

The following table describes the labels in this screen. 

A port forwarding set is a list of inside (behind NAT on the LAN) servers, for example, web or 
FTP, that you can make visible to the outside world even though NAT makes your whole 
inside network appear as a single computer to the outside world. 
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. You can allocate a server IP address that 
corresponds to a port or a range of ports.
Many residential broadband ISP accounts do not allow you to run any server processes (such 
as a Web or FTP server) from your location. Your ISP may periodically check for servers and 
may suspend your account if it discovers any active services at your location. If you are 
unsure, refer to your ISP.

In addition to the servers for specified services, NAT supports a default server IP address. A 
default server receives packets from ports that are not specified in this screen.

Table 31   NAT General

Active 

Network 

Address 

Translation 

(NAT)

Select this check box to enable NAT.

SUA Only

Select this radio button if you have just one public WAN IP address for your ZyXEL 

Device. 

Full Feature 

Select this radio button if you have multiple public WAN IP addresses for your ZyXEL 

Device. 

Max NAT/

Firewall 

Session Per 

User

When computers use peer to peer applications, such as file sharing applications, they 

need to establish 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 

ZyXEL Device.
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 Apply to save your changes back to the ZyXEL Device.

Cancel

Click Cancel to reload the previous configuration for this screen.