Re: [v6ops] draft-ietf-v6ops-host-addr-availability discussion

David Farmer <farmer@umn.edu> Tue, 03 November 2015 01:55 UTC

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To: Brian E Carpenter <brian.e.carpenter@gmail.com>, "Templin, Fred L" <Fred.L.Templin@boeing.com>, Lorenzo Colitti <lorenzo@google.com>
From: David Farmer <farmer@umn.edu>
Organization: University of Minnesota
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Date: Mon, 2 Nov 2015 19:55:39 -0600
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Subject: Re: [v6ops] draft-ietf-v6ops-host-addr-availability discussion
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On 11/2/15 19:46 , Brian E Carpenter wrote:
> On 03/11/2015 14:31, Templin, Fred L wrote:
>> Bumping up one level – is it clear to everyone that it is OK to assign addresses
>> taken from a DHCPv6 delegated prefix to the interface over which the prefix
>> was received?
>
> If it was legitimately received, I can't see why it wouldn't be OK.
>
>> And, that DAD is not required for those addresses?
>
> How is that safe? What is to stop a host running SLAAC once it
> sees that prefix in an RA, and hitting the same IID by chance?
> At least you need to specify that the A bit must not be set.
>
> Come to that, a manual address might collide.

And no one has ever screwed up their pseudo-random number generation 
code. :(

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