Information:
DansGuardian is a filtering proxy that uses Squid to do the fetching. It filters using four methods:
It checks the actual content of the pages
against a configurable denied phrase list. This list contains profanities and phrases often associated with pornography and other undesirable content
It implements PICS filtering
It checks the MIME type of the requested file and checks this against a configurable denied MIME type list
It checks the file extension of the requested file against a
configurable denied file extension list
The filtering has a configurable URL exception list. It does not implement a URL check against a list of sites like squidGuard; it checks the actual content of the pages. DansGuardian is free for non-commercial use.