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

Philip Homburg <> Sun, 27 October 2019 15:05 UTC

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Date: Sun, 27 Oct 2019 16:05:35 +0100
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Subject: Re: [v6ops] SLAAC renum: Problem Statement & Operational workarounds
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> Indeed, this would also
> not actually solve the problem.   At present, the ISPs are doing
> something that is out of spec and causes problems.   If we fix this
> by accommodating what they do, does that help, or does it just
> encourage them to continue doing it?

At the moment, ISPs are doing something that sort of works in IPv4 because
of NAT. It causes significant issues in IPv6.

Of course, can we can tell ISPs that they are doing it wrong and that they
should not deploy IPv6 until they have fixed their networks.

I would like to have IPv6 now. And if that requires some tweaks to deal with
broken behavior then so be it.

> If you Really Really want to be able to have the routers send out
> RAs that deprecate the default route, and, as Mark is saying here,
> to upgrade millions or perhaps billions of hosts, why not ask for
> something thats a real improvement?

Because bundling features is a good way to ensure that nothing gets done.

Dealing with flash renumbering in the CPE is a relatively small tweak that
can be implemented at any time.

> Second, fix RA so that its
> non-repudiable by a device that doesnt have the secret key.

If you think that this is an important thing to fix, feel free to 
talk about it. But why in this discussion? SEND doesn't do anything for
flash renumbering. From an operational point of view, RA-guard is much
more attractive then SEND. So it is not clear to me that there is any
need for SEND. But I could be wrong. In any case, if there is a need
to discuss SEND we could do that separately.

This discussion is on how to deal with flash renumbering.