Blocking Yahoo Messenger, AOL Messenger, etc.

[ksowell]

How can messenger services like yahoo, AOL, and MSN be blocked from internal users?

[gjackson]

There is an article in InfoSec magazine which covers this to some degree. Quite frankly, it's not an easy task.

http://www.infosecuritymag.com/articles/february01/cover.shtml

Good luck.

[brad-denham]

You can try to block access for the following:

AOL - aimexpress.oscar.aol.com, login.oscar.aol.com, toc.oscar.aol.com

MSN - chat.msn.com, messenger.hotmail.com

ICQ - login.icq.com

Yahoo - chat.yahoo.com, scs-fooa.yahoo.com, scs-foob.yahoo.com, scs-fooc.yahoo.com, scs-food.yahoo.com, scs-fooe.yahoo.com, and scs-foof.yahoo.com

I am doing it for my organization at our firewall and I have at excellent results.