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

Fernando Gont <fgont@si6networks.com> Sat, 11 November 2017 03:06 UTC

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Subject: Re: [v6ops] Stateful SLAAC (draft-ietf-v6ops-unique-ipv6-prefix-per-host)
To: Ted Lemon <mellon@fugue.com>, DY Kim <dykim6@gmail.com>
Cc: IPv6 Operations <v6ops@ietf.org>, "6man@ietf.org" <6man@ietf.org>, "6man-ads@tools.ietf.org" <6man-ads@ietf.org>, "v6ops-ads@ietf.org" <v6ops-ads@ietf.org>, draft-ietf-v6ops-unique-ipv6-prefix-per-host@tools.ietf.org
References: <be9724f5-2ff5-d90c-2749-ecae2c628b78@si6networks.com> <CAKD1Yr0_a2Qm8U4oK+BQU57DeDUD9i-o_+G+YhnH4pVXRxmxxQ@mail.gmail.com> <BBB987EF-D91C-4FD1-9084-21382F24E7BF@gmail.com> <37b58331-ecfc-aaf8-bde4-91dd4d375834@si6networks.com> <029B5A33-0C3F-4021-BA86-50E6DF37F879@gmail.com> <59F47233-62ED-489D-9421-00128C8E7EB2@fugue.com>
From: Fernando Gont <fgont@si6networks.com>
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Date: Sat, 11 Nov 2017 00:05:13 -0300
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On 11/10/2017 11:45 PM, Ted Lemon wrote:
> The issue is that if you have allocated a prefix for a host and then you reboot the router, either you retain the allocation in stable storage, or you don't.   If you don't, how do you make sure that the host doesn't get renumbered?
> 
> That's the sense in which this is stateful, whereas SLAAC by itself is not.   It's not really SLAAC that's stateful—it's the mapping between the link-local SLAAC address and the prefix that's assigned to the host.

If the SLAAC router needs to keep that state, why do you say that it is
not SLAAC that is stateful? Whose state is that, then?

Thanks,
-- 
Fernando Gont
SI6 Networks
e-mail: fgont@si6networks.com
PGP Fingerprint: 6666 31C6 D484 63B2 8FB1 E3C4 AE25 0D55 1D4E 7492