Re: Node Requirements: Elevating DHCPv6 from MAY to SHOULD

Philip Homburg <pch-6man@u-1.phicoh.com> Mon, 30 May 2011 20:27 UTC

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To: Markus Hanauska <hanauska@equinux.de>
Subject: Re: Node Requirements: Elevating DHCPv6 from MAY to SHOULD
From: Philip Homburg <pch-6man@u-1.phicoh.com>
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In-reply-to: Your message of "Mon, 30 May 2011 12:47:19 +0200 ." <3044C560-F46C-477A-BD87-DF252F689FAB@equinux.de>
Date: Mon, 30 May 2011 22:27:16 +0200
Cc: "ipv6@ietf.org" <ipv6@ietf.org>
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In your letter dated Mon, 30 May 2011 12:47:19 +0200 you wrote:
>Then a node has both, a SLAAC address and a DHCPv6 address. Where is the probl
>em? The only problem I can think of is the issue I was trying to discuss here 
>a couple of weeks ago: An address collision between SLAAC addresses and non-SL
>AAC addresses. Normal SLAAC should never collide with DHCP, since the 'u' bit 
>is always 1 for a SLAAC address (globally unique) but should be '0' for a DHCP
> address (not globally unique). Only SLAAC with Privacy Extension could collid
>e with DHCP (since it also has a 'u' bit of 0) and I was told on this list "Do
>n't worry, the address space is so huge, this is probably never going to happe
>n". 

If you are really worried about this, then I guess you can also just assign
two prefixes to a single link and use one for SLAAC and the other for DHCPv6.