Digi TransPort WR11, Руководство пользователя

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Configure security settings Firewall
Digi TransPort WR Routers User Guide 685
Firewall
To configure firewall settings, go to Configuration > Security> Firewall .
About firewalls
All Digi TransPort routers incorporate a comprehensive firewall facility. A firewall is a security
system for restricting the type of traffic that the router will transmit or receive based on a
combination of IP address, service type, protocol type, port number and IP flags. Firewalls minimize
the risk of unauthorized access to the local network resources by external users or to restrict the
range of external resources to which local users have access. For a more detailed description of how
firewalls operate on Digi routers, see Firewall scripts . Refer that section before attempting to
implement a firewall.
The rules governing the operation of the firewall are contained in a pseudo-file called
fw.txt . This
file can be created either by using the controls in the web page described below or by using a text
editor on a PC and then loading the resulting file onto the router using FTP or XMODEM. Digi Routers
are shipped with a default fw.txt file you can use as the starting point for a custom firewall
configuration.
Firewall parameters
Firewall configuration is performed on the Configuration > Security> Firewalls page.
Parameter descriptions follow . There are three other buttons that appear just below the table.
Their use will also be described.
Since a default file is supplied, when this page loads it displays the rules in the default
fw.txt file. If
fw.txt does not exist, a blank table is displayed.
Hits
The numbers that appear in this column of the table are the number of hits for the rule that
appears to the right.
#
This is non-editable and is simply the rule number.
Delete
Clicking this button deletes the rule that appears to its left.
Insert
The insert buttons that appear alongside existing rules insert new blank lines above the line on
which they appear. The button at the bottom creates a new blank line at the end of the table. (An
empty table will only have the one button at the bottom). To create a new rule, click the button
at the point the new rule should appear and a new text box should appear. Type the rule into the
text box and once complete, click the OK button. To abandon any changes click the Cancel
button. Once the OK button has been clicked the firewall task will validate the rule and if valid,
will add it the table. If errors are detected, a warning message will be displayed, at which point
the rule may be edited or deleted.