the alleged evils of NAT, was Rate of growth on IPv6 not fast enough?

David Conrad drc at
Sat May 1 01:26:01 UTC 2010


On Apr 29, 2010, at 8:29 AM, Paul Timmins wrote:
> If you change ISPs, send out an RA with the new addresses, wait a bit, then send out an RA with lifetime 0 on the old address.

Even if this works (and I know a lot of applications that use the socket() API that effectively cache the address returned by DNS for the lifetime of the application), how does this help situations where IPv6 address literals are specified in configuration files, e.g., resolv.conf, glue for authoritative DNS servers, firewalls/filters, network management systems, etc.?  See sections 5 and 7 of

The point here is that if there is a non-zero cost associated with renumbering, there will be non-zero incentive to deploy technologies such as NATv6 to reduce that cost.  Some folks have made the argument that for sites large enough for the cost of renumbering to be significant, they should be able to justify provider independent space and be willing to accept the administrative and financial cost. While this may be the case (I have some doubts that many of the folks using PA space now will be all that interested in dealing with the RIR system, but I may be biased), it does raise concerns about routing system growth and forces ISPs to be willing to accept long IPv6 prefixes from end users (which some ISPs have already said they won't do).


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