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

Fernando Gont <> Sun, 27 October 2019 16:30 UTC

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To: Mark Smith <>, Owen DeLong <>
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From: Fernando Gont <>
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Date: Sun, 27 Oct 2019 13:29:32 -0300
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Subject: Re: [v6ops] SLAAC renum: Problem Statement & Operational workarounds
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On 27/10/19 04:57, Mark Smith wrote:
> So in summary, the proposal is to update RFCs, change 100s of millions
> of CPE implementations, and billions of IPv6 host implementations, to
> accommodate some ISPs who want to cling to an obsolete dynamic and
> dial up origin address provisioning model for always on Internet
> connections?

Once more: the CPE router case is just *one of many* scenarios that may
lead to the problem described in the document.

The discussion about CPEs has to do with the CPEs doing what is right --
regardless of whether the ISP renumbers or not.

Robustness has a lot to do with being able to gracefully handle the case
when others screw up.

> Robustness is useful, however there needs to be a determined threshold
> where, beyond that, the cost of adding robustness exceeds the cost of
> properly fixing the problem that created the need for additional
> robustness in the first place.

Could you please point at any specific part of the document that you
object to?

> Making all CPE and all IPv6 hosts more robust to work around a problem

What we describe is what CPEs should be doing to respect the protocol

Fernando Gont
SI6 Networks
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