
An example of the default DansGuardian blocking message.
'DansGuardian' is a
content control system, primarily authored by
Daniel Barron, the technical director of
SmoothWall Ltd. It is distributed under the
GPL, and written in
C++. It primarily runs in
Linux and other
Unixes. It is entirely command line and web-based, and meant to be used in conjunction with a web proxy such as
Squid. In the
United States, DansGuardian satisfies the requirements of
Children's Internet Protection Act.
DansGuardian has multiple configurable methods of deciding whether or not to show a specific
web page. It can use an advanced phrase weighting system to reduce over or under blocking, block based on URL blacklists, and block content based on the
PICS code in the document. The program can use phrase lists (keywords) and URL block lists provided in plain text format, such as the one provided by a URLBlacklist.com which provides, on subscription basis, URL lists for DansGuardian and
SquidGuard. DansGuardian also ships with a workable phrase list. See the
introduction page on the official web site for more information about filtering methods used.
DansGuardian is one of the few widely used filtering/content control systems that makes its
source code available, thus avoiding some of the criticisms associated with content control system proxies being "
black box" systems.
Two
closed-source versions of DansGuardian exist; SmoothGuardian is a
plug-in for
SmoothWall Corporate Server Firewall, and Corporate Guardian is a stand-alone
product.
See also
★
Internet censorship
★
Content-control software
External links
★
DansGuardian Website
★
squidGuard Website
★
URLBlacklist