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DAD question

"Fred Baker (fred)" <fred@cisco.com> Fri, 10 August 2012 22:17 UTC

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From: "Fred Baker (fred)" <fred@cisco.com>
To: "ipv6@ietf.org 6man" <ipv6@ietf.org>
Subject: DAD question
Thread-Topic: DAD question
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Date: Fri, 10 Aug 2012 22:17:15 +0000
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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)?

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