Administrator's Guide - Kerio Software Archive

HTTP and FTP filtering
13.1 Conditions for HTTP and FTP filtering
For HTTP and FTP content filtering, the following conditions must be met:
1. Traffic must be controlled by an appropriate protocol inspector.
An appropriate protocol inspector is activated automatically unless its use is denied by
traffic rules. For details, refer to chapter 7.3.
2. Connections must not be encrypted. SSL encrypted traffic (HTTPS and FTPS protocols)
cannot be monitored. In this case you can block access to certain servers using traffic
rules (see chapter 7.3).
3. FTP protocols cannot be filtered if the secured authentication (SASO) is used.
4. Both HTTP and FTP rules are applied also when the Kerio Control’s proxy server is used
(then, condition 1 is irrelevant). However, FTP protocol cannot be filtered if the parent
proxy server is used (for details, see chapter 9.4). In such a case, FTP rules are not applied.
5. If the proxy server is used (see chapter 9.4), It is also possible to filter HTTPS servers (e.g.
https://secure.kerio.com/). However, it is not possible to filter individual objects at
these servers.
13.2 URL Rules
These rules allow the administrator to limit access to Web pages with URLs that meet certain
criteria. They include other functions, such as filtering of web pages by occurrence forbidden
words, blocking of specific items (scripts, active objects, etc.) and antivirus switch for certain
pages.
To define URL rules, go to the URL Rules tab in Configuration → Content Filtering → HTTP
Policy.
Figure 13.1
URL Rules
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