ZyXEL Communications VMG8825-B Series, Руководство пользователя, Страница: 173 / 360

Chapter 11 Network Address Translation (NAT)
VMG8825-B Series User’s Guide
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For example:
Figure 88 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 VMG to record Jane’s computer IP address. The VMG
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 VMG 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 VMG
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
VMG’s trigger port settings.
Figure 89 Network Setting > NAT > Port Triggering
DSL