What ports can be blocked to stop chat rooms and instant messaging?

[Christopher Chan]

Ernest L. Williams Jr. wrote:
> Hi
> 
> Which port does one block to stop all AIM and chat room related network
> activity from going in or out?
> 
> 
> 

Simple. Just choose the protocols you want to allow to flow through and 
setup rules to allow those. Then block everything else.

Otherwise, you will have to go round to ICQ, Yahoo and MSN websites (and 
who knows what else?) and hunt for their protocol information on their 
respective instant messenging client software.