I have taken over as admin for a company that has built an extensive internal network on the 128.x.x.x network. When I resolve these addresses without using a host file, I get machines, switches, and routers at the Carnege Mellon University. My boss says it is no big deal because we are behind a firewall and we are not publishing the internal addresses. My question, is the use of public IP's on an internal network and issue and if so, what verbiage can I use to convince my boss of that fact. I have always built my own networks or have taken over rathe properly configured networks so I have never had to make this argument.