Re: Updated IID length text

Lorenzo Colitti <lorenzo@google.com> Thu, 19 January 2017 04:08 UTC

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From: Lorenzo Colitti <lorenzo@google.com>
Date: Thu, 19 Jan 2017 13:07:50 +0900
Message-ID: <CAKD1Yr0JTJNJ8ApcY0zBdbKuvUAx2H57WThGr4pcVP1OLt-OMA@mail.gmail.com>
Subject: Re: Updated IID length text
To: "Manfredi, Albert E" <albert.e.manfredi@boeing.com>
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On Thu, Jan 19, 2017 at 12:24 PM, Manfredi, Albert E <
albert.e.manfredi@boeing.com> wrote:

> > The reason it can't do that is that in practice SLAAC only works well
> > if the probability of collision is negligible. Even reducing that from
> > 64 bits to 48 bits impacts that substantially.
>
> Perhaps, but SLAAC has been deemed to work adequately well with only the
> 48-bit MAC address (presumably) being unique. So nothing would change in
> this "negligible collision" regard, if we allowed for 80-bit prefixes with
> SLAAC. You'd want to do duplicate address detection regardless.
>

No, the situation with MAC addresses is different because they are intended
to be unique.