Thus spake "Keith Moore" <moore@cs.utk.edu> > > And you're conflating ambiguous addressing with scoping. > > nope. the property that I'm concerned about is not that an address > may only be usable within a particular portion of the network, it's > that the address is ambiguous. As Mr. Hain pointed out, last week your argument was about scoping and apps picking addresses, not about private addresses. > so given an address there's no way to know whether or not it is valid, > or why it doesn't seem to work to let you connect with the > host/peer/server you think it's associated with. You have no way of knowing if any address is reachable from any particular location. That is not a property specific to private addresses. > > Perhaps. There is no functional difference unless multiple instances > > of the same address are actually _reachable_ by a third party; the > > mere existence of duplicates does not change the architecture. > > wrong. it's useful to have unique names for hosts (or points on the > network) even if they're not directly reachable by everyone who might > possess those names. Useful, yes; a fundamental part of the architecture, no. Removing private addresses from the IPv6 architecture is a fundamental change from IPv4: site-locals are not a new addition, just a different name. If site-locals are deprecated, the NAT/stable address/whatever crowd will just pick a different prefix to use. Worst case, they'll all pick different ones. RFC1597 didn't cause the scoped-address mess; it just provided a reasonably safe sandbox and standard semantics. S Stephen Sprunk "God does not play dice." --Albert Einstein CCIE #3723 "God is an inveterate gambler, and He throws the K5SSS dice at every possible opportunity." --Stephen Hawking