On Wed, Apr 4, 2012 at 6:31 PM, Steven Bellovin <smb@xxxxxxxxxxxxxxx> wrote: > > On Apr 4, 2012, at 5:21 35PM, Noel Chiappa wrote: > >>> From: Doug Barton <dougb@xxxxxxxxxxxxx> >> >>> My comments were directed towards those who still have the mindset, >>> "NAT is the enemy, and must be slain at all costs!" >> >> In semi-defense of that attitude, NAT (architecturally) _is_ a crock - it puts >> 'brittle' (because it's hard to replicate, manage, etc) state in the middle of >> the network. Having said that, I understand why people went down the NAT road >> - when doing a real-world cost/benefit analysis, that path was, for all its >> problems, the preferable one. > > NAT didn't really exist when the basic shape of v6 was selected. Perhaps, but that it would happen is obvious (even to the most causal observer). Dave >> >> Part of the real problem has been that the IETF failed to carefully study, and >> take to heart, the operational capabilities which NAT provided (such as >> avoidance of renumbering, etc, etc), and then _failed to exert every possible >> effort_ to provide those same capabilities in an equally 'easy to use' way. > > They thought -- or claimed -- that they had renumbering... > > v6 is not the protocol I would have chosen. For that matter, it's not the > protocol I pushed for, as hard as I could, in the IPng directorate. At this > point -- with all of its technical mistakes, IETF omissions, and difficulty > of converting, we're stuck with it; we simply do not have time -- even if > we agreed now on what we should have done, way back when -- to start over. > Do the arithmetic... Assume we know, today, the basic structure of a > perfect replacement for v4. It would take a minimum of 3 years to get > through the IETF, not because of process but because there are so many > things that it touches, like the DNS, BGP, OSPF, and more. There are > also all of the little side-pieces, like the ARP/ND replacement, the PPP > goo, etc. After that, it's 3 years of design/code/test by Microsoft, > Apple, Cisco, Juniper, et al., following which we have the whole education > cycle, the replacement cycle while old boxes die off and are replaced, and > more. (Look at how many Windows XP boxes still exist -- and we're well > into the second major release of Windows since then, and Windows 8 might > be out before the end of the year.) By my arithmetic, it's a dozen years > minimum, *after* we've agreed on the basic design. > > > --Steve Bellovin, https://www.cs.columbia.edu/~smb > > > > >