ZyXEL Communications eircom D1000, User Manual

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126
eircom D1000 modem U
ser’s Guide
Chapter 9 Network Address Translation (NAT)
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.
Finding Out More
See Section 9.6 on page 130 for advanced technical information on NAT.
9.2 The NAT General Screen
Use this screen to activate NAT for the default WAN connection (PVC0). Click Network Setting >
NAT to open the following screen.
Note: You must create an IP filter rule in addition to setting up NAT, to allow traffic from
the WAN to be forwarded through the Device.
Figure 85
Network Setting > NAT > General
The following table describes the labels in this screen.
Table 42
Network Setting > NAT > General
LABEL DESCRIPTION
Active Select this check box to enable NAT.
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 client computers can establish through the 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 this to save your changes.
Cancel Click this to restore your previously saved settings.