ZyXEL Communications ZyWall USG 2000 User Manual page 542

Chapter 33 Content Filtering
Content Filtering Profiles
A content filtering profile conveniently stores your custom settings for the
following features.
• Category-based Blocking
The ZyWALL can block access to particular categories of web site content, such
as pornography or racial intolerance.
• Restrict Web Features
The ZyWALL can disable web proxies and block web features such as ActiveX
controls, Java applets and cookies.
• Customize Web Site Access
You can specify URLs to which the ZyWALL blocks access. You can alternatively
block access to all URLs except ones that you specify. You can also have the
ZyWALL block access to URLs that contain particular keywords.
Content Filtering Configuration Guidelines
When the ZyWALL receives an HTTP request, the content filter searches for a
policy that matches the source address and time (schedule). The content filter
checks the policies in order (based on the policy numbers). When a matching
policy is found, the content filter allows or blocks the request depending on the
settings of the filtering profile specified by the policy. Some requests may not
match any policy. The ZyWALL allows the request if the default policy is not set to
block. The ZyWALL blocks the request if the default policy is set to block.
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.
Keyword Blocking URL Checking
The ZyWALL checks the URL's domain name (or IP address) and file path
separately when performing keyword blocking.
The URL's domain name or IP address is the characters that come before the first
slash in the URL. For example, with the URL
pressroom.php, the domain name is www.zyxel.com.tw.
The file path is the characters that come after the first slash in the URL. For
example, with the URL www.zyxel.com.tw/news/pressroom.php, the file path is
news/pressroom.php.
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www.zyxel.com.tw/news/
ZyWALL USG 2000 User's Guide