Chapter 31 Content Filter Screens

Table 148 Anti-X > Content Filter > Filter Profile (continued)

LABEL

DESCRIPTION

Add

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.

 

 

Apply

Click Apply to save your changes back to the ZyWALL.

 

 

Reset

Click Reset to begin configuring this screen afresh.

 

 

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

1A computer behind the ZyWALL tries to access a web site.

2The 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.

3Use 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 Section 31.9 on page 480). All of the web site address records are also cleared from the local cache when the ZyWALL restarts.

4If 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.

5The 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

 

ZyWALL USG 1000 User’s Guide