Dean Anderson wrote: > ... > Allowing a non-global address space as a subset of the global space means > that one (or many) can reach the public network through a default route > that leads to a NAT. But if you have such a large network that it has > something greater than 20 million hosts ^^^^^^^ Fatal flaw... The concept of a network is not limited to the traditional perspective of 'hosts'. > that must each have direct access > to any of the rest, and you can't NAT internally, then you probably have > reached a point where you will need a more sophisticated mechanism than > NAT to reach the public internet. You assume a network & traffic model that may not apply. > > Underlying this is the question of whether such a large network really > needs to simultanously reach the public network. If it doesn't, then there > is no reason to limit oneself to the RFC 1918 space. Yes there is when some of the nodes do need access to the public network. You can't expect to use a private version of a publicly routed prefix. > > I might also suggest that such a heavy address user migrate to IPv6 > internally as IPv6 has similar problems and it is developing means to deal > with them. Easy to say, but turning something with that mass takes more time than the dentist office network. Yes it is the right thing to do, but don't expect it to happen in a timeframe shorter than 3-5 years. Tony _______________________________________________ Ietf@xxxxxxxx https://www1.ietf.org/mailman/listinfo/ietf