Two Points To Remember About Trigger Ports - ZyXEL Communications MWR222 - V1.0 Manual

Figure 88 Trigger Port Forwarding Process: (it shows MWR-222)
Example
Jane requests a file from the Real Audio server (port 7070).
1
Port 7070 is a "trigger" port and causes the MWR222 to record Jane's
2
computer IP address. The MWR222 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
3
6970-7170.
The MWR222 forwards the traffic to Jane's computer IP address.
4
Only Jane can connect to the Real Audio server until the connection is
5
closed or times out. The MWR222 times out in three minutes with UDP
(User Datagram Protocol), or two hours with TCP/IP (Transfer Control
Protocol/Internet Protocol).

13.5.2 Two Points To Remember About Trigger Ports

Trigger events only happen on data that is going coming from inside the
1
MWR222 and going to the outside.
2 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.
MWR222 User's Guide
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