I know this is subtle but if you take a step back, user-mode TCP/IP moots the policies we're talking about; it doesn't subvert them. There are no security or policy implications to e.g. binding a low-numbered port on an IP address unrelated to your physical computer that is allocated directly to a running instance of your program. There are (archaic) implications to binding that port on an actual interface of your machine, because that binding (archaically) stood in for an assertion of identity/authority back in the 1990s.