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Re: Why has RFC 4941 been designed in such a way, that it might cause address conflicts?

Brian E Carpenter <brian.e.carpenter@gmail.com> Tue, 15 March 2011 22:53 UTC

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Date: Wed, 16 Mar 2011 11:54:30 +1300
From: Brian E Carpenter <brian.e.carpenter@gmail.com>
Organization: University of Auckland
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To: james woodyatt <jhw@apple.com>
Subject: Re: Why has RFC 4941 been designed in such a way, that it might cause address conflicts?
References: <C744C51B-F2B0-4137-B39F-54B8D62F1C97@equinux.de> <E7CFEDBC-5048-413E-93C9-DBF79B4FC238@apple.com> <E8CD61BF-827E-4A83-AA63-275D0CCB0B53@equinux.de> <35A891E0-9BA1-4694-AFA3-C6C46C8F3625@apple.com>
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On 2011-03-16 09:35, james woodyatt wrote:
...
> No certainty is possible.  Duplicate Address Detection (DAD) is your last best hope for civilization.

If you'll excuse an anecdote, while I was living in Geneva I was regularly
amused when the shiny new information screens in the shiny new buses
would display the Windows IPv4 duplicate address warning instead of
the next bus stop. Even so, the Geneva bus service hasn't come to an end.

My point? The probability of a duplicate address in an IPv6 subnet is
many orders of magnitude less than it is in IPv4. Like 1 in 2^63
instead of 1 in 2^8.

This is just too remote a probability to worry about.

   Brian

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