> presuming there is no firewall or nat between the client and the server That's one of the issues though. If you can't access a machine via its internal IP, m

> presuming there is no firewall or nat between the client and the server That's one of the issues though. If you can't access a machine via its internal IP, many useful usage patterns break. Someone complained that the issue is that services aren't secure, but there's more to it than that: good security depends on defense in depth, and firewalls are an important part of that.