Re: [v6ops] Stateful SLAAC (draft-ietf-v6ops-unique-ipv6-prefix-per-host)

DY Kim <> Sat, 11 November 2017 02:29 UTC

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Subject: Re: [v6ops] Stateful SLAAC (draft-ietf-v6ops-unique-ipv6-prefix-per-host)
From: DY Kim <>
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Date: Sat, 11 Nov 2017 11:29:26 +0900
Cc: Fred Baker <>, Lorenzo Colitti <>, IPv6 Operations <>, "" <>, "" <>, "" <>,
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To: Fernando Gont <>
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I don’t get it when you say this doc makes SLAAC stateful.

‘Staleless’ in SLAAC applies to hosts, not necessarily to routers.

Your argument might be based on the text of the draft, 2nd last para of Sec. 5:

  "IPv6 SLAAC requires the router to maintain neighbor state, which implies costs in terms of memory, power, message exchanges, and message processing."

For routers to keep (address) information about the hosts does not make SLAAC stateful. In order to manage (keep track of) the hosts that use SLAAC, routers need to store some information about the host. This action of the router is natural and has nothing to to with the ‘stateless’ property of SLAAC, AFAIU.

See also, for example, the beginning of the 2nd para of Sec. 1, RFC 4862:

  "The IPv6 stateless autoconfiguration mechanism requires no manual configuration of hosts, minimal (if any) configuration of routers, and no additional servers.”

I don’t think the text in Sec. 5 of the doc, as repeated above, does not make SLAAC stateful.


> On 11 Nov 2017, at 05:23, Fernando Gont <> wrote:
> THe main issue is not this but, as the subject implies, this document
> making SLAAC stateful.