Chapter 10 Network Address Translation (NAT) Screens

Figure 91 NAT General

The following table describes the labels in this screen.

Table 53 NAT General

LABEL

DESCRIPTION

Active

Select this check box to enable NAT.

Network

 

Address

 

Translation

 

(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/

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

Firewall

need to establish NAT sessions. If you do not limit the number of NAT sessions a

Session Per

single client can establish, this can result in all of the available NAT sessions being

User

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 client computers 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

 

exhausting 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.

 

 

10.4 Port Forwarding

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.

 

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P-2602HWLNI User’s Guide