Subject: Re: IPv6 Comment
To: None <current-users@netbsd.org, kenh@cmf.nrl.navy.mil>
From: Sean Doran <smd@ebone.net>
List: current-users
Date: 09/02/2000 17:11:01
kenh writes:

| I've seen the same IPv6 "discussion" on the ietf mailing list that
| you've been in the middle of ... and I know that no one there ever said
| that "renumbering easily" was a benefit of IPv6.  

To quote from draft-iab-case-for-ipv6-06.txt, with the _IAB_'s imprimatur,
which I imagine you can find easily enough in your favourite I-D archive:

   Finally,
   renumbering IPv4 sites when changing from one ISP to another,
   in order to maintain and improve address/route aggregation, is
   significantly more expensive and difficult compared with IPv6's site
   renumbering capabilities (see section 1.2.3).

and

   A key aspect of IPv6's eased
   renumbering capability is its built-in support for multiple
   simultaneous addresses.  This capability allows a site to migrate
   to a new numbering scheme slowly while continuing to support the
   previous numbering scheme.  Only when migration to the new addresses
   is complete, are the old addresses retired.  In contrast, with IPv4,
   renumbering a network involves having a ``flag day'' -- that is, a
   day when work stops and the network administrators are faced with
   making a huge conversion. 

and so forth ( 1.3.7, 1.3.9, 2.12 ... ...).  

Renumbering is clearly a touted benefit of IPv6 vs IPv4, and it is
touted by exactly the same set of people you see downplaying the
ease of renumbering of IPv6 on the IETF list, viz. then-members
and current members of the IAB.

Note that the "Myth #9" was not in several previous drafts, yet
still starts off with "IPv6 has gone a long way to enable more
convenient renumbering".  Also note that the observations in that
myth are directly applicable to renumbering using NAT.

| Plenty of people smarter than I have said this before to you.  I could
| believe that some IPv6 evangelists might have said something like
| "renumbering is easier with IPv6" at one time, but either they
| misunderstood things or you misinterpreted their statements. 

Please go explain this to the IAB, then!

	Sean.