Moin, am 06.10.19 um 10:59 schrieb Gert Doering: > Hi, > > On Sun, Oct 06, 2019 at 12:38:14AM +0200, Kai 'wusel' Siering wrote: >> If 240/4 is to be given a different status than "reserved", the >> only valid option is "public unicast", spread across the RIRs as >> recovered space. As has been stated here may times, IPv4 is here >> to stay, so it's vital that relevant amounts of "new" space are put >> into the public pool. > I'd actually say "private" is a better denomination. > > To make this useful as "public unicast", you need to upgrade *everything* > in the path between a device using 240/4 and "whatever it wants to talk to", > because un-upgraded routers or firewalls will just drop your packets > otherwise - so, if RIPE were to give out a subnet of 240/4, it would not > be very useful for "Internet" usage.
I didn't say it would be a quick win; I'm aware of the issues. 240/4 space would remain of limited reachability for the forseeable future. After being declared to become public space via an RFC, devices that still receive updates will learn about 240/4, thus lessening the reachablility issue over time, though. Rationale: an internal network needing more than 16 million IPv4 addresses (10/8) does have the power to solve their addressing needs with IPv6. This isn't true for newcomers that have to deal with old players not enabling v6. Please note: I'm not proposing do touch 240/4, 0/8 or 127/8, but _if_ those are touched, they should be given to the public. Regards, -kai