block chatting How ??

Hi,

Tell them not to. From management.

The instant messenging services available today can be put to quite good use for work purposes - on occasions. So disabling it altogether might not be the best solution.

If management agrees that the use of chatting for personal reasons during work time is not allowed, then they should be ready to back up that statement with appropriate action.

Sticking your head in the sand (filtering or disabling MSN content) isn't always the best way to strongly lead...

Cheers,
Tim.

First point to block them is the firewall. By default, MSN requires a huge number of ports to be open (everything above 1024 really, although it will only use one of these ports, randomly selected). Each of the various chat clients uses a different port for authentication (ICQ uses 5190, for example). However, most chat protocols support HTTP proxies.

Your best bet is to firewall them in, so they can't directly connect on the necessary ports. On your proxy server, disallow access to the key sites required by these clients (ICQ needs to get to login.icq.com, for example).

I don't have a specific list for each protocol, but you would need to take a two-level approach like this to get the results you are looking for.