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Re: DAD question

"Fred Baker (fred)" <fred@cisco.com> Sat, 11 August 2012 20:11 UTC

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From: "Fred Baker (fred)" <fred@cisco.com>
To: Ole Trøan <otroan@employees.org>
Subject: Re: DAD question
Thread-Topic: DAD question
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Date: Sat, 11 Aug 2012 20:11:06 +0000
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On Aug 11, 2012, at 12:04 PM, Ole Trøan wrote:

>>>> Call this "making sure I'm on the same page as anyone else"…
>>>> 
>>>> RFC 4941 describes privacy addresses, and RFC 4291 describes an EID based on a MAC Address. RFC 4862 describes stateless address autoconfiguration, and uses RFC 4861's duplicate address detection mechanism.
>>>> 
>>>> My question is: what happens if any of them discovers that it has created an address that is already in use in the network?
>>>> 
>>>> There would appear to be two options: 
>>>> (1) "ah, OK, I guess I didn't really want to talk today"
>>>> (2) Following RFC 4941, guess again until one creates a unique address
>>>> 
>>>> Is it fair to assume that implementations do DAD and follow (2)?
>>> 
>>> implementations I'm familiar with do 1.
>>> it may be a fair assumption that if an address based on the MAC address is duplicate, the MAC address itself is a duplicate.
>> 
>> And that relates to privacy addresses how?
> 
> it doesn't. is your question how DAD is done for privacy addresses?

My question is for all addresses. I'm getting responses for MAC addresses.

> then section 3.3 of RFC4941 is quite clear on that.
> 
> cheers,
> Ole

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