Special Applications - 3Com OfficeConnect 3C855 User Manual

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Special Applications

Figure 37 Special Applications Screen
Select Special Applications tab to display Authorized Application setup screen.
(Figure 37)
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.
To configure special access:
1 Click on the New button.
2 Select the applications from the pull-down list. (Figure 38)
Figure 38 Special Application Settings Screen
Or select Other to specify a suitable name for the special application and then
enter a value in the Trigger and Incoming Ports text boxes. (Figure 39) These values
correspond to the outbound port number issued by the application.
The port numbers are specified using a comma-separated list, with hyphens to
denote port number ranges. So for example, entering 2, 3, 5-7 would cause ports
2, 3, 5, 6, and 7 to be activated.
The Gateway will automatically allow FTP and NetMeeting sessions. You do not
need to configure these as Special Applications.