Chat block using pix 501

[shariff_99]

please sugget or post configuration as how to block chat programs like MSN, YAHOO using PIX 501 for internal users. I have a network of 40 users connected to internet through pix 501. As of now inbound connections are controlled by default NO access. Outbound is also default as it allows everyone to access internet. I just want to block chat for internal users . that is outbound connections of CHATTING. Please suggest the methods.

thanks

[sachinraja]

Hi shariff,

some chat programs use port 80 as default to get connected..

first thing you need to do is to allow only port 80 traffic on the PIX and block the rest of them.. this will block most of the unnecessary programs.

access-list inside permit tcp host 192.168.1.10 (proxy) any eq http

acess-list inside permit tcp host 192.168.1.10 any eq https

(implicit deny)

anyway, you can try doing these:

you can block MSN by tcp port 1863.

access-list inside deny tcp 192.168.1.0 255.255.255.o any eq 1863

If this doesnt work, try this:

1. In the registry, navigate to: \HKUR\Software\Microsoft\MessengerService\

2. Find the item named Server: messenger.hotmail.com;64.4.13.50:1863. Change this value to Null;0.0.0.0:0

That's it.

yahoo messenger uses port 80.. thats the problem .. in case you have a proxy.. try blocking this site, msg.edit.yahoo.com/*,messenger.yahoo.com/*andhttp.pager.yahoo.com/*

you have a lot of softwares now, which can block P2P, chat programs etc. try one of them, if u need.

Hope this helps.. all the best..

Raj