If you are using IPv4 address that belong to someone else internally you really are in a prime position to use IPv6 only internally and use one of the IPv4AAS mechanisms to reach the IPv4 internet. After a quarter of a century all your equipment should be IPv6 capable. -- Mark Andrews
On 1 Feb 2024, at 19:57, Owen DeLong via NANOG <nanog@nanog.org> wrote:
On Jan 31, 2024, at 23:19, Frank Habicht <geier@geier.ne.tz> wrote:
On 01/02/2024 01:45, Tom Beecher wrote: Seems a bit dramatic. Companies all over the world have been using other people's public IPs internally for decades. I worked at a place 20 odd years ago that had an odd numbering scheme internally, and it was someone else's public space. When I asked why, the guy who built it said "Well I just liked the pattern." If you're not announcing someone else's space into the DFZ, or otherwise trying to do anything shady, the three letter agencies aren't likely to come knocking. Doesn't mean anyone SHOULD be doing it, but still.
Well...
If you're using 20.20.20.0/24 which is not "yours" (as I've seen happen), then certainly your customers can't get to the real 20.20.20.x And even if that's not announced and used /today/ - this can change quickly...
Frank
You are repeating exactly the argument I made at the time.
Owen