On 2011-03-21 11:00, Hemant Singh (shemant) wrote:
> -----Original Message-----
> From: ipv6-boun...@ietf.org [mailto:ipv6-boun...@ietf.org] On Behalf Of
> Brian E Carpenter
> Sent: Tuesday, March 15, 2011 6:55 PM
> To: james woodyatt
> Cc: ipv6@ietf.org
> Subject: Re: Why has RFC 4941 been designed in such a way, that it might
> causeaddress conflicts?
>
>
>> 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.
>
> In a recent IPv6 CE Router Interop in the U.S. during mid-February 2011
> where such home routers were tested in a cable broadband network IPv6
> link-local addresses were found to be duplicate. My guess is that the
> Interop network had 2-30 IPv6 nodes. Two different CE routers with
> different mac-addresses created the same IPv6 link-local address. I
> don't have logs from the problem but the problem can only be one of two
> things. Either the CE did not generate its IPv6 link-local address
> using EUI-64 or the CE did but the CE has a bug in the code to generate
> an IPv6 link-local address using the EUI-64 format that uses the
> mac-address of the CE. The CE routers are consumer devices that will
> deploy with no console. So what admin of the network will see the CE
> reporting to the CE console a DAD failure for the IPv6 link-local
> address? The SP serving this home is also clueless as to what
> happened!
>
> Stuff happens.
Yes, and paradoxically this illustrates my point. Passing a law that
addresses shall not conflict, or shall only conflict with a probability
of 1 in 2^63, is beside the point.
Others on this thread have reported they want to secure
> their IPv6 networks. We should collect a list of all issues operators
> of networks and other folks are reporting and see if the existing
> protocols are not able to help, let's see what else we can do.
Good idea, where's the wiki?
Brian
--------------------------------------------------------------------
IETF IPv6 working group mailing list
ipv6@ietf.org
Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6
--------------------------------------------------------------------
