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Configure firewall filters
You can only configure filters in the »Professional Configurator«.
User-defined filters for the router integrated into the PABX system with packet filter firewalls can be configured un-
der Network / Filters.
Note
We recommend configuring the firewall filters with the aid of the Filter Wizard to ensure configuration(s) appro-
priate for and compatible to the applications being used. These filters provide protection against data packets from
the Internet that may result in you being charged for certain connections. The function for the “Automatic connec-
tion setup”, for example, may otherwise not always be ensured. A port scan from the Internet (usually the initial sta-
ge of a hack attack) may sometimes occur; the telephone system firewall then replies to this scan with »Reject pa-
ckets«. But this may nevertheless result in data traffic that prevents automatic setup of a connection.
Note
The filters available using the Filter Wizard have been implemented using the latest knowledge. We can, however,
provide no guarantee for the function of the filters. Use of a firewall should go hand in hand with use of virus scan-
ning software on all your PCs! Firewalls and virus scanners cover different areas of data security and are an ideal
compliment to one another, but can not replace one another.
To configure self-defined filters click the button “New ...” or change an existing entry in the filter list by double cli-
cking on that item. An explanation of the filter function is given when you click on “Help”.
Basic information about firewall configuration
It is important that you have detailed knowledge about the IP protocol family before you begin configuring the fire-
wall. If your knowledge about this is not so in-depth we recommend using a filter wizard.
The firewall functions like a chain of rules
through which each IP packet is routed. If a rule
applies to a packet the action associated with this
rule will be executed (allow, deny or execute port-
map). All rules are given in the list under Net-
work / Filters. Please note that for certain confi-
gurations the order of the filters can be of great
significance for the functioning of the firewall.
Therefore, after you mark a filter rule you can de-
fine the order of the rules in the table using the
buttons [up] and [down].
If no rule applies to the IP packet a super-ordinate, basic rule at the end of the chain decides on the action to be taken
(behavior by last filter rule).
This is why you must define the behavior.. .. .. for this super-ordinate rule at the beginning of the filter configuration.
You can choose between »Allow« or »Discard« for this.
Configure firewall filters
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