Re: Accidental ARIN Reallocation

[William Herrin via NANOG <nanog () lists nanog org>]

On Wed, Dec 17, 2025 at 11:08 AM Christopher Morrow
<morrowc.lists () gmail com> wrote:
> On Wed, Dec 17, 2025 at 12:06 AM William Herrin via NANOG
> <nanog () lists nanog org> wrote:
> I don't think, really, there was ever any REAL hope that 100.64 was

> > If you know it's 4.10 space (not address space allocated under a
> > different policy section) and you know they're using it for plain IPv4
> > or generic dual stack, please file a report at
> > https://account.arin.net/public/fraud
>
> Is it abuse/fraud if the LIR is treating this as RFC1918 / private space?

Hi Chris,

Did I miss the part where we pivoted to talking about RFC 6598 space?
I thought we were talking about ARIN NRPM 4.10 space.

An ISP can employ 100.64.0.0/10 (RFC 6598 space) any way they choose.
ARIN is not a party to that process. It's usually not a good idea to
use 100.64.0.0/10 for anything other than numbering downstream
customers in conjunction with CGNAT, but that's an operational choice
for the ISP.

Regards,
Bill Herrin


--
For hire. https://bill.herrin.us/resume/
_______________________________________________
NANOG mailing list 
https://lists.nanog.org/archives/list/nanog () lists nanog org/message/GTAR4AOYC4XAM3JMNPNFGKCT7RKY5X6A/