We have a corporate network that is comprised of the following elements:
Internet cable (wall) <-> (ext interface (DHCP))(Windows Server 2008, TMG-enabled, Internet Gateway)(int interface (static 192.168.0.1) <-> Internal Ethernet Network with Windows-based DHCP server, DNS, etc.
I have a gutt feelling that time after time a laptop is being brought by someone in the office that has a static IP, the same as our Gateway (192.168.0.1) set on it's ethernet adapter which causes our server to have a communication problem with the rest of the network. If it's a MacOS or Linux, I've heard that they for some reason can "steal" the IP even if one is already present in the network. Is it true and how can I protect our server from "outsiders with the same IP"?