ZyXEL Communications MWR211, Manual, Page: 141 / 340

MWR211 User’s Guide
141
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 MWR211 to record Jane’s
computer IP address. The MWR211 associates Jane's computer IP address
with the "incoming" port range of 6970-7170.
3
The Real Audio server responds using a port number ranging between
6970-7170.
4
The MWR211 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 MWR211 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
1
Trigger events only happen on data that is going coming from inside the
MWR211 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.