ZyXEL NBG-318S Guia Do Utilizador

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 Chapter 10 Network Address Translation (NAT)
NBG-318S User’s Guide
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Figure 67   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 NBG-318S to record Jane’s computer IP 
address. The NBG-318S 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 NBG-318S 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 NBG-318S 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 NBG-318S 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 NBG-318S’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.