Re: Updated IID length text

Brian E Carpenter <brian.e.carpenter@gmail.com> Thu, 19 January 2017 03:23 UTC

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Subject: Re: Updated IID length text
To: "Manfredi, Albert E" <albert.e.manfredi@boeing.com>, 6man <ipv6@ietf.org>
References: <148406593094.22166.2894840062954191477.idtracker@ietfa.amsl.com> <m2fukqbbwv.wl-randy@psg.com> <F6953234-3F85-4E28-9861-433ADD01A490@gmail.com> <m2wpdzhncn.wl-randy@psg.com> <82245ef2-cd34-9bd6-c04e-f262e285f983@gmail.com> <m2d1frhjfn.wl-randy@psg.com> <18e6e13c-e605-48ff-4906-2d5531624d64@gmail.com> <CAKD1Yr1cvZ8Y3+bHeML=Xwqr+YgDspZGnZi=jqQj4qe2kMc4zw@mail.gmail.com> <m2lguffnco.wl-randy@psg.com> <CAKD1Yr1TrTiPRdyutobmb_77XJ7guNzLrg=H_p7qi4BfQ8V=GA@mail.gmail.com> <m2d1frfm6m.wl-randy@psg.com> <CAKD1Yr2Njjd8_Mr+6TRFF6C5pdcX4yFgpFVyEkykDuytu2B8mg@mail.gmail.com> <2A5073777007277764473D78@PSB> <4596c3d4-a337-f08e-7909-f14270b7085f@gmail.com> <CAN-Dau06R3iYRpYLADhvHox4C9qdsJCuxFsJapRhOQcWT4qk_g@mail.gmail.com> <CAO42Z2weZcoHiBzN94QAQ9WGhWR16PmMMFNg=5YLmr_dhPjjpA@mail.gmail.com> <fcc7f136-b5da-527e-b495-5a2d7f7a3ce8@gmail.com> <55bb8bdbfbf4439da0aa702e5bc03e2c@XCH15-06-11.nw.nos.boeing.com> <bb79ce41f2cc465dab0a7f26466be26f@XCH15-06-11.nw.nos.boeing.com>
From: Brian E Carpenter <brian.e.carpenter@gmail.com>
Organization: University of Auckland
Message-ID: <ed9fe2df-0dce-0ddc-bdee-561217d089bb@gmail.com>
Date: Thu, 19 Jan 2017 16:23:55 +1300
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On 19/01/2017 15:55, Manfredi, Albert E wrote:
...
>> I don't think that SLAAC *must* require a single standard IID length, so
>> that's why I added the word "robust." Now that we have moved away from using
>> the MAC address for SLAAC, it's not clear to me why a host cannot wait for a
>> RA, and then decide on how many IID bits to use, based on the prefix
>> length(s) advertised by the router.

Not if you want to form a link-local address first. Which you always do,
because perhaps there *is* no router when you come up after a power cut.
(In the Anima WG, we are very interested in the behaviour of nodes
that have absolutely no external information when they come up, because
it's their job to bootstrap the network out of nowhere.)

    Brian