Re: Extending a /64

[Tony Whyman <[e-mail]>]

On 19/11/2020 11:30, Nick Hilliard wrote:
> the key phrase is:
>
> Mark Smith wrote on 19/11/2020 05:22:
>> [...] without any intention to ever
>>     directly connect to other enterprises or the Internet itself.
>
> If the ICAO can guarantee that ipv6 assignments to aircraft will never 
> be used to directly connect to other third party networks, then ULA 
> will work fine. I doubt that this is a safe assumption.
>
> Nick
>
Correct, this is not a safe assumption. Also, a 40-bit global ID does 
not allow us enough remaining bits. We could set the L bit to 0 and then 
use our own format - but happens if an internet (e.g. a military one) 
wants to do the same, or another RFC comes along and defines a new ULA 
format with L=0? All that we would really be doing is to squat on a 
portion of the global address space and this is not what we should be doing.