I wonder if anyone can help me, I have a Vigor 2820 router on which I am trying to restrict internet access. I also have a ISA proxy server that I want users to access the internet through.
So far I have blocked all LAN->WAN access for all ports then added further rules to allow servers access to the internet, which works fine.

The users have now requested access to use MSN messenger during certain times of the day, which I know CSM on the 2820 should be capable of doing.

Could any one point in the right direction for the exact configuration I need to get the firewall to allow MSN at certain times but then block all other internet traffic so that users are forced to browse through the ISA server.

Many Thanks in advance
Matt Reay