Figure 15-7 Trigger Port Forwarding Process: Example; Figure 15-8 Trigger Port - ZyXEL Communications ZyWALL 5 User Manual

Figure 15-7 Trigger Port Forwarding Process: Example

Jane requests a file from the Real Audio server (port 7070).
1.
Port 7070 is a "trigger" port and causes the ZyWALL to record Jane's computer IP address. The
2.
ZyWALL associates Jane's computer IP address with the "incoming" port range of 6970-7170.
The Real Audio server responds using a port number ranging between 6970-7170.
3.
The ZyWALL forwards the traffic to Jane's computer IP address.
4.
Only Jane can connect to the Real Audio server until the connection is closed or times out. The
5.
ZyWALL times out in three minutes with UDP (User Datagram Protocol) or two hours with
TCP/IP (Transfer Control Protocol/Internet Protocol).
To change your ZyWALL's trigger port settings, click SUA/NAT and the Trigger Port tab. The
screen appears as shown.
The following table describes the labels in this screen.
NAT

Figure 15-8 Trigger Port

ZyWALL 5 Internet Security Appliance
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