Re: Extending a /64

[Mark Smith <[e-mail]>]

On Fri, 20 Nov 2020, 09:27 Nick Hilliard, <[e-mail]> wrote:

> Mark Smith wrote on 19/11/2020 19:56:
> > What makes you think that once you have a high order prefix, you have
> > the freedom to arbitrarily define the format and semantics of any of the
> > low order bits?
>
> the cart needs to go before the horse.
>
> If Tony is saying that ipv6 assignments to aircraft could - even
> possibly - be used to directly connect to other third party networks,
> then ULA is inappropriate and we can park that discussion.


ULAs are specifically designed to allow interconnecting to other ULA
networks without resorting to renumbering or IPv6 NAT.

That is why the Global ID is required to pseudo-random, so that when two
ULA networks are interconnected, there is no overlapping or duplicate
address space. Subnet prefixes and therefore the hosts attached to them
already have globally unique addresses, even though they don't have global
reachability or access.

This was one of the problems with site-locals. Merging two site-local
address spaces would have involved renumbering or NAT.




This leaves
> GUA or something else from other IANA-reserved address space.
>
> Thing is, if an organisation feels that their needs for ip address
> allocation are sufficiently different from everyone else's in the world
> that they need to bypass the RIRs and apply for a direct IANA
> reservation - whether that be in GUA space or not - then the
> organisation needs to make a case which justifies this ask.
>
> Obviously there's no problem discussing ideas on 6man to get the lay of
> the land, but bypassing the RIRs for addressing requirements seems to be
> an extraordinary ask, and an extraordinary request will need
> extraordinary justification.
>
> Nick
>