Re: Happy St Nicholas Day: Re-Launching the IPv6 ULA registry

[Fernando Gont <[e-mail]>]

On 7/12/20 19:30, Nico Schottelius wrote:
[....]
> fd00::/48 is actually an example entry created during the Hackathon,
> which led us to implement the random generation instead as the primary
> option instead of focussing on submission of existing prefixes.
> 
>> In fact, I just configured it on my network, so if
>> there was no duplicate before, there is one now. :-)
> 
> With that argument even GUA is not GUA - I can also configure 2600::/32
> or even 2001:db8::/32 in my network, it does not make me "own" 2600::/32
> nor remove the documentation character from 2001:db8::/32.

FWIW, for all practical purposes, ULAs are non-global-scope addresses -- 
the only reason (?) they are considered global is that RFC4291 still 
marks the ULA "space" as GUA, and RFC4193 hasn't updated that.

So, an ULA is not meant to be globally usable, and only make sense 
within an organization (whatever that means) -- and the same ULA prefix 
being re-used is just fine.

OTOH, GUAs are globally-meaningful -- and while you can indeed configure 
any GUA prefix you want, you will not get the return traffic (which you 
*would* if you really owned the prefix).

Thanks,
-- 
Fernando Gont
SI6 Networks
e-mail: [e-mail]
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