ZyXEL nbg-334w Guia Do Utilizador

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 Chapter 10 Network Address Translation (NAT)
NBG334W User’s Guide
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Figure 66   Trigger Port Forwarding Process: Example
Jane requests a file from the Real Audio server (port 7070).
Port 7070 is a “trigger” port and causes the NBG334W to record Jane’s computer IP 
address. The NBG334W 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.
The NBG334W 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 NBG334W times out in three minutes with UDP (User Datagram Protocol), or 
two hours with TCP/IP (Transfer Control Protocol/Internet Protocol). 
10.5.2  Two Points To Remember About Trigger Ports
Trigger events only happen on data that is going coming from inside the NBG334W and 
going to the outside.
If an application needs a continuous data stream, that port (range) will be tied up so that 
another computer on the LAN can’t trigger it.
10.6  NAT Advanced Screen
To change your NBG334W’s trigger port settings, click Network > NAT > Advanced. The 
screen appears as shown.
"
Only one LAN computer can use a trigger port (range) at a time.