ZyXEL Communications VMG4325-B10A, User Manual

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Chapter 11 Network Address Translation (NAT)
VMG4380-B10A / VMG4325-B10A User’s Guide
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For example:
Figure 80
Trigger Port Forwarding Process: Example
1
Jane requests a file from the Real Audio server (port 7070).
2
Port 7070 is a “trigger” port and causes the Device to record Jane’s computer IP address. The
Device associates Jane's computer IP address with the "open" port range of 6970-7170.
3
The Real Audio server responds using a port number ranging between 6970-7170.
4
The Device forwards the traffic to Jane’s computer IP address.
5
Only Jane can connect to the Real Audio server until the connection is closed or times out. The
Device times out in three minutes with UDP (User Datagram Protocol) or two hours with TCP/IP
(Transfer Control Protocol/Internet Protocol).
Click Network Setting > NAT > Port Triggering to open the following screen. Use this screen to
view your Device’s trigger port settings.
Figure 81
Network Setting > NAT > Port Triggering
The following table describes the labels in this screen.
Table 58
Network Setting > NAT > Port Triggering
LABEL DESCRIPTION
Add new rule Click this to create a new rule.
# This is the index number of the entry.
Status This field displays whether the port triggering rule is active or not. A yellow bulb signifies
that this rule is active. A gray bulb signifies that this rule is not active.
Service Name This field displays the name of the service used by this rule.
WAN Interface This field shows the WAN interface through which the service is forwarded.
Trigger Start
Port The trigger port is a port (or a range of ports) that causes (or triggers) the Device to record
the IP address of the LAN computer that sent the traffic to a server on the WAN.
This is the first port number that identifies a service.
Trigger End
Port This is the last port number that identifies a service.
Trigger Proto. This is the trigger transport layer protocol.