IP Masquerading is the act of hiding an entire network behind a single machine. Basically, the IP Masquerading host takes all the packets from one side of the network and passes them on to the other side ”like any router. Unlike routers, however, the IPMasq host rewrites each packet so that it appears as if the IPMasq host itself sent it. When it receives a reply to one of these rewritten packets, it rewrites it once again, passing it back to the correct host on the hidden network. This means that for a single valid IP address, you can have dozens, hundreds, or even thousands of machines with full access to the other side ”all while remaining completely hidden.