3Com WL-537 User Manual page 66

70 C 5: R C
HAPTER OUTER ONFIGURATION
Special Applications Special Applications Screen
Select Special Apps tab to display Authorized Application setup screen.
Some software applications require special or multiple connections to the
Internet and these would normally be blocked by the firewall. For
example Internet Telephony or Video conferences require multiple
connections.
So that these special applications can work properly and are not blocked,
the firewall needs to be told about them. In each instance there will be a
trigger port and incoming port(s), where traffic on the trigger port tells
the firewall to open the incoming ports.
Each defined Special Application only supports a single computer user,
and up to 10 Special Applications can be defined. Any incoming ports
opened by a Special Application trigger will be closed after five minutes
of inactivity.
Special Application allows the router to keep track of outgoing data for
specific port numbers. The router remembers which computer sends out
what data, so when the requested data returns through the router, the
data is sent back to the proper computer by way of IP address and port
mapping rules.
Click Save to save the setting.