Blocking instant messaging sites
Novell Cool Solutions: Question & Answer
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Q:
What is the best way to block instant messaging sites, such as AOL Instant Messenger, MSN Messenger, ICQ, Yahoo! Messenger, and Google Talk?
A:
Most chat sites use port 80, so blocking by port would not work. You'll
simply need to start adding the various URLs for these sites to a BorderManager "deny URL" rule, OR purchase a commercial piece of software that can help with this, such as LinkWall (www.connectotel.com) or SurfControl. If you're looking for a public blacklist, try here:
http://www.squidguard.org
It's strongly recommend you read tip #47 at http://www.craigjconsulting.com. You usually cannot just filter your way around this.
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