Re: Ephemeral addressing [was Re: 64share v2]

Fernando Gont <> Thu, 12 November 2020 16:07 UTC

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Subject: Re: Ephemeral addressing [was Re: 64share v2]
To:, Philip Homburg <>
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From: Fernando Gont <>
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Date: Thu, 12 Nov 2020 13:03:08 -0300
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On 11/11/20 10:35, wrote:
> Philip,
>> Or just stick to static prefixes.
> Seems to me the world waited. At least the one I'm leaving in did. :-)

Most leaf IP networks are not exposed to renumbering since they use 
private address space.

That's different for IPv6. My home network gets regularly renumbered, 
and I experience draft-ietf-v6ops-slaac-renum.

> None of the systems I use handle renumbering. Barring a single application (mosh).
> Most of the building blocks are there, but in 20 years of waiting few if any have put them together.

The current mechanisms rely on state in all intervening network devices, 
and the signaling mechanism is unreliable. That makes the network fragile.

> I doubt this is deployable in time to avoid users being forced to NAT on the edge, to protect themselves from instability in global addressing.

If we get to, at the very lest, do more timely garbage collection as in 
draft-ietf-6man-slaac-renum, that would already be a big improvement.

> Are we going to restrict all future IPv6 end-user networks that are forced to depend on PA addressing to be client only?

Many end-user IPv6 networks are restricted to client-only. Because the 
CE Router implements a firewall, and there's no UPnP IPv6 support (or 
similar) that allows nodes to punch holes in the firewall.

Ironically, in such scenarios IPv4 ends up having better 
e2e-connectivity properties than IPv6.

Fernando Gont
SI6 Networks
PGP Fingerprint: 6666 31C6 D484 63B2 8FB1 E3C4 AE25 0D55 1D4E 7492