External Web Filtering Service; Figure 350 Content Filter Lookup Procedure - ZyXEL Communications Unified Security Gateway ZyWALL 1000 User Manual

Chapter 31 Content Filter Screens
Table 148 Anti-X > Content Filter > Filter Profile (continued)
LABEL
Add
Apply
Reset

31.5 External Web Filtering Service

When you register for and enable the external web filtering service, 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 filter lookup process is described below.

Figure 350 Content Filter 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
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 queries the external content filter
database and simultaneously sends the request to the web server.
5 The external content filter server sends the category information back to the ZyWALL,
which then blocks and/or logs access to the web site based on the settings in the content
filter profile. The web site's address and category are then stored in the ZyWALL's
content filter cache.
468
DESCRIPTION
Click the Add icon at the top of the column to create a new content filter
profile at the end of the list.
Click a content filter policy's Add icon at the to create a new content filter
policy below the current line. All other entries below the new entry are
pushed down.
Click Apply to save your changes back to the ZyWALL.
Click Reset to begin configuring this screen afresh.
Section 31.9 on page 480). All
ZyWALL USG 1000 User's Guide