3 content filtering with an external database, Figure 155 content filtering lookup procedure – ZyXEL Communications 5 Series User Manual
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Chapter 16 Content Filtering Screens
16.3 Content Filtering with an External Database
When you register for and enable external database content filtering, your ZyWALL accesses
an external database that has millions of web sites categorized based on content. You can have
the ZyWALL block, block and/or log access to web sites based on these categories. The
content filtering lookup process is described below.
Figure 155 Content Filtering Lookup Procedure
1 A computer behind the ZyWALL tries to access a web site.
2 The ZyWALL looks up the web site in its cache. If an attempt to access the web site was
made in the past, a record of that web site’s category will be in the ZyWALL’s cache. The
ZyWALL blocks, blocks and logs or just logs the request based on your configuration.
3 Use the CONTENT FILTER Cache screen to configure how long a web site address
remains in the cache as well as view those web site addresses (see
). All of the web site address records are also cleared from the local cache when the
ZyWALL restarts.
4 If the ZyWALL has no record of the web site, it will query the external content filtering
database and simultaneously send the request to the web server.
The external content filtering database may change a web site’s category or categorize a
previously uncategorized web site.
From
Type the beginning IP address (in dotted decimal notation) of the specific
range of users on your LAN.
To
Type the ending IP address (in dotted decimal notation) of the specific range
of users on your LAN, then click Add Range.
Address List
This text field shows the address ranges that are blocked.
Add Range
Click Add Range after you have filled in the From and To fields above.
Delete Range
Click Delete Range after you select the range of addresses you wish to
delete.
Apply
Click Apply to save your changes back to the ZyWALL.
Reset
Click Reset to begin configuring this screen afresh.
Table 88 SECURITY > CONTENT FILTER > General
LABEL
DESCRIPTION