Re: [v6ops] Implementation Status of PREF64

[Lorenzo Colitti <[e-mail]>]

On Thu, Sep 30, 2021 at 11:16 AM Owen DeLong <owen=
[e-mail]> wrote:

> Nonetheless, restoring the e2e addressing model and true peer-to-peer
> networking _IS_, in fact, worth the effort and expense IMHO.
>

Owen, I think you need to realize that IPv6 by itself does not provide
end-to-end addressing. It only provides end-to-end addressing *if
sufficient addresses are available*, and if *it's possible to inform
devices of network configuration changes*. DHCP as currently managed and
deployed is terrible at both those things. Yes, I know it's possible to
*sort of* make DHCPv6 do this via reconfigure, multiple DUIDs, etc., but
current implementations and operational models do not do this.

As for network changes - sure, it's possible to ensure that things don't
change, like an enterprise network that uses PI space.

But as for sufficient addresses... as you said yourself in this thread,
(some) operators want to use DHCPv6 in order to ensure a single address per
device. This will *not* result in end-to-end connectivity. It will result
in the device getting that single address running NAT66 and and and all the
other functions inside that device or connected to it getting private IPv6
addresses and non-end-to-end connectivity. We tried to write this down in RFC
7934 sections 3 and 4
<https://datatracker.ietf.org/doc/html/rfc7934#section-3>.

So again: if all we're getting from the transition to IPv6 is 128-bit IPv4
with NAT, then why bother?