-----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. 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. Hemant -------------------------------------------------------------------- IETF IPv6 working group mailing list ipv6@ietf.org Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
