Chapter 8 Network Address Translation (NAT)
P-870H/HW Series User’s Guide
128
8.6 The DMZ Host Screen
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 the
NAT Port Forwarding Setup screen.
Figure 70
NAT > DMZ Host
The following table describes the fields in this screen.
8.7 The ALG Screen
Some NAT routers may include a SIP Application Layer Gateway (ALG). A SIP ALG
allows SIP calls to pass through NAT by examining and translating IP addresses
embedded in the data stream. The SIP ALG translates the ZyXEL Device’s private
IP address inside the SIP data stream to a public IP address. You do not need to
use STUN or an outbound proxy if you enable the SIP ALG.
Table 41
NAT > DMZ Host
LABEL
DESCRIPTION
Default Server
Enter the IP address of the default server which receives packets from
ports that are not specified in the NAT Port Forwarding screen.
Note: If you do not assign a
Default Server
, the ZyXEL Device
discards all packets received for ports that are not specified
in the
NAT Port Forwarding
screen.
Apply
Click Apply to save your changes back to the ZyXEL Device.
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