Is there a way (software or hardware) to disconnect or cut off a user's lan connection if they use their modem to dial out to an ISP? We have a very secure LAN setup, but our only failing point is that several users w/in the LAN, have modems on their pc's which they use legitamately for product testing. I can not isolate these pc's off the LAN, due to other applications and databases that the users need, but everytime they dial out, they are completely bypassing every firewall, router and other security measures we have setup. I can not rely on, nor do I trust the end user to be security minded when they log on to their ISP's. Is there any measure that I can take to protect our network while not interfereing with the legitimate use of the modems????