Re: DAD question

Ole,

On Aug 11, 2012, at 1:33 AM, Ole Trøan wrote:

> Fred,
> 
>> 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.

True, but the odds of this happening are very low.  I wonder if we have any data on DAD detecting duplicate addresses and their cause.

For example, has any seen any actual duplicate MAC addresses?  It would be good to collect some data.

Bob

> 
> cheers,
> Ole--------------------------------------------------------------------
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