ZyXEL 2WG Guida Utente

Chapter 13 Content Filtering Screens

ZyWALL 2WG User’s Guide

Figure 170   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. 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. 

5 The external content filtering server sends the category information back to the 

ZyWALL, which then blocks and/or logs access to the web site. The web site’s address 
and category are then stored in the ZyWALL’s content filtering cache.

Click SECURITY > CONTENT FILTER to open the General screen.
Use this screen to enable content filtering and configure general settings. You must register for 
external content filtering before you can use it. Use the REGISTRATION screens (see 

) to create a myZyXEL.com account, register your device and activate 

the external content filtering service.