Re: [v6ops] SLAAC renum: Problem Statement & Operational workarounds

Philip Homburg <pch-v6ops-9@u-1.phicoh.com> Sun, 27 October 2019 19:05 UTC

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In-reply-to: Your message of "Sun, 27 Oct 2019 16:03:38 +0100 ." <44F39DE2-E142-4ED0-853E-2F3AAC6F4ADE@employees.org>
Date: Sun, 27 Oct 2019 20:04:45 +0100
Archived-At: <https://mailarchive.ietf.org/arch/msg/v6ops/gWVQdkG4a4Hov3HUk6VBRnCdf8I>
Subject: Re: [v6ops] SLAAC renum: Problem Statement & Operational workarounds
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> > In this particular case (a CPE rebooting and getting a different prefix fro
> m
> > the ISP), SLAAC has for the most part what we need.
> >
> > The little bit missing is that the CPE should write prefixes advertised usi
> ng
> > SLAAC to persistent storage which allows the CPE to invalidate stale prefix
> es
> > after a reboot.
> >
> > Note that we could change SLAAC to allow the lifetime of a prefix to be
> > set to zero, instead of having to wait for 2 hours. That might be an
> > improvement but requires careful analsysis.
> 
> Can you explain how operating a public service should work on this
> type of network?

Could you be more specific what you consider a 'public service' and what
you expect to break?

What I described is basically what happens on IPv4 when a CPE uses NAT 
and gets a new IPv4 address from the ISP.

Flash renumbering is far from ideal, but a reality on the current internet.
Any application that is suitable for home use is expected to deal with that
scenario.

Note that with automatic DNS updates, you can probably run a mail server (or
your personal 'cloud') on such a link. But that is not a common use case
at the moment.