Dynamic Web Content Filtering - D-Link DFL-260E User Manual

6.3.4. Dynamic Web Content Filtering

6. Enter */*.exe in the URL textbox
7. Click OK
Finally, make an exception from the blacklist by creating a whitelist:
1. Go to Objects > ALG
2. In the table, click on the recently created HTTP ALG to view its properties
3. Click the HTTP URL tab
4. Now click Add and select HTTP ALG URL from the menu
5. Select Whitelist as the Action
6. In the URL textbox, enter www.D-Link.com/*.exe
7. Click OK
Simply continue adding specific blacklists and whitelists until the filter satisfies the needs.
6.3.4. Dynamic Web Content Filtering
6.3.4.1. Overview
As part of the HTTP ALG, NetDefendOS supports Dynamic Web Content Filtering (WCF) of web
traffic, which enables an administrator to permit or block access to web pages based on the content
of those web pages.
Dynamic WCF Databases
NetDefendOS Dynamic WCF allows web page blocking to be automated so it is not necessary to
manually specify beforehand which URLs to block or to allow. Instead, D-Link maintains a global
infrastructure of databases containing huge numbers of current web site URL addresses which are
already classified and grouped into a variety of categories such as shopping, news, sport,
adult-oriented and so on.
The Dynamic WCF URL databases are updated almost hourly with new, categorized URLs while at
the same time older, invalid URLs are dropped. The scope of the URLs in the databases is global,
covering websites in many different languages and hosted on servers located in many different
countries.
WCF Processing Flow
When a user of a web browser requests access to a web site, NetDefendOS queries the Dynamic
WCF databases in order to retrieve the category of the requested site. Access to the URL can then be
allowed or denied based on the filtering policy that the administrator has put in place for that
category.
If access is denied, a web page will be presented to the user explaining that the requested site has
been blocked. To make the lookup process as fast as possible NetDefendOS maintains a local cache
in memory of recently accessed URLs. Caching can be highly efficient since a given user
Dynamic WCF is only available on certain NetDefend models
Dynamic WCF is only available on the D-Link NetDefend DFL-260, 260E, 860, 860E,
1660, 2560 and 2560G.
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Chapter 6. Security Mechanisms