User Manual

Chapter 9 WAN
NBG6818 User’s Guide
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Note: TCP port 7547 is reserved for system use.
Note: The maximum number of trigger ports for a single rule or all rules is 999.
Note: The maximum number of open ports for a single rule or all rules is 999.
Figure 49 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 Zyxel Device to record Jane’s computer IP address. The Zyxel
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 Zyxel Device forwards the traffic to Jane’s computer IP address.Only Jane can connect to the Real
Audio server until the connection is closed or times out. The Zyxel Device times out in three minutes with
UDP (User Datagram Protocol) or two hours with TCP/IP (Transfer Control Protocol/Internet Protocol).
Use this screen to view the summary table of your NBG6818’s port trigger settings. Click Expert Mode >
WAN > NAT > Port Trigger to show the following screen.
Note: Only one LAN computer can use a trigger port (range) at a time.
Figure 50 Expert Mode > WAN > NAT > Port Trigger
The following table describes the labels in this screen.
Table 28 Expert Mode > WAN > NAT > Port Trigger
LABEL DESCRIPTION
Port Trigger Rules (Max Limit: 32)
No. This is the rule index number.