On 20/1/21 18:10, John Levine wrote:
In article <CAMm+LwjNiE0P7RAVqzKMypNbh3=9BeqiWn_hGv3E=zX7-YmSXQ@xxxxxxxxxxxxxx> you write:
The proposal is to reserve a significant block of IPv6 space (e.g.
2002::/16) as non routable address space to be allocated in Class A/B/C
sized chunks on a permanent basis either through random assignment or by a
new registrar TBD for a negligible one-time fee ($0.10 or less). This would
provide significant operational benefits for large enterprises managing
complex networks.
This sounds a lot like ULAs. You generate a 40 bit random number,
prefix it with FD and that's your own /48. If you have a decent random
number genarator the chances of your 40 bit number colliding with
anyone else's are insignificant. See RFC 4193.
No. Collissions are actually almost guaranteed (birthday paradox).
What the spec says is that *if you grab a handful of ULA networks* they
(not the entire ULA universe) are quite unlikely to collide.
I gather the problem in practice is that rather than a 40 bit random
number, too many people use one that spells something cute or
memorable in hex.
That's correct -- non-compliant with RFC4193, but still correct.
Thanks,
--
Fernando Gont
SI6 Networks
e-mail: fgont@xxxxxxxxxxxxxxx
PGP Fingerprint: 6666 31C6 D484 63B2 8FB1 E3C4 AE25 0D55 1D4E 7492
