ZyXEL Communications EX3510-B1, User Manual

Page: 176 / 313

Chapter 11 Network Address Translation (NAT)
EX3510-B1 User’s Guide
176
Note: Use an IPv4 address for the DMZ server.
Note: Enter the IP address of the default server in the Default Server Address field, and click
Apply to active the DMZ host. Otherwise, clear the IP address in the Default Server
Address field, and click Apply to deactivate the DMZ host.
Figure 104 Network Setting > NAT > DMZ
The following table describes the fields in this screen.
11.5 ALG Settings
Application Layer Gateway (ALG) allows customized NAT traversal filters to support address and port
translation for certain applications such as File Transfer Protocol (FTP), Session Initiation Protocol (SIP), or
file transfer in Instant Messaging (IM) applications. It allows SIP calls to pass through the Zyxel Device.
When the Zyxel Device registers with the SIP register server, 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 your Zyxel Device is behind a SIP ALG.
Use this screen to enable and disable the ALGs in the Zyxel Device. To access this screen, click Network
Setting > NAT > ALG .
Table 62 Network Setting > NAT > DMZ
LABEL DESCRIPTION
Default Server
Address 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 Address , the Zyxel Device discards all
packets received for ports that are not specified in the NAT Port Forwarding
screen.
Cancel Click Cancel to restore the default or previously saved settings.
Apply Click Apply to save your changes.