Re: Looking for an IPv6 naysayer...

[William Herrin <bill () herrin us>]

On Wed, Feb 9, 2011 at 3:05 PM, Iljitsch van Beijnum <iljitsch () muada com> wrote:
> On 9 feb 2011, at 20:53, William Herrin wrote:
> > * Carrier NAT buys us enough years to build an IPv4 successor
>
> You're kidding, right? How long did it take exactly to get where
> we are now with IPv6? 18, 19 years?

Tech like carrier NAT theoretically yeilds address reclamation in
excess of 80%. Internet-facing servers must consume IP address. It's
convenient for client computers to do so as well, but not critical to
the general function of the Internet. 20 years is about what that
level of reclamation buys before we're out of addresses again. As you
say -- enough time to develop a protocol and get it into the software
and hardware.


> > * Next protocol should really be designed to support interoperability
> > with the old one from the bottom up. IPv6 does not
>
> That's because it's not the headers that aren't incompatible (the
> protocol translation is ok even though it could have been a bit
> better) but the addresses.

No, it's because decisions were made to try to abandon the old DFZ
table along with IPv4 and institute /64 as a standard subnet mask. But
for those choices, you could directly translate the IPv4 and IPv6
headers back and forth, at least until one of the addresses topped 32
bits. The transition to IPv6 could be little different than the
transition to 32-bit AS numbers -- a nuisance, not a crisis. You
recompile your software with the new IN_ADDR size and add IP header
translation to the routers, but there's no configuration change, no
new commands to learn, etc.

Regards,
Bill Herrin



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William D. Herrin ................ herrin () dirtside com  bill () herrin us
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