Martin Millnert millnert at gmail.com
Mon Jan 31 23:00:08 CST 2011


I have not heard of any IP stack that is built to accept 240/4.
Neither Linux 2.6.37 nor Windows 7 accepts it, and let's not think
about all routers, including CPE:s, out there.
The logic goes:
You are many orders of magnitudes more likely to get v6 off the
ground, than 240/4 or 224/4 as unicast IPv4.  224/3 will never be very
usable as public v4 space since every non-upgraded host on the
Internet will be unable to send packets to them, eg, for every
additional host you introduce with these addresses the worse the
reachability situation becomes for the v4 Internet. Notably, this is
the inverse of what happens when you introduce more hosts with native,
proper IPv6, in the IPv6-Internet.


On Mon, Jan 31, 2011 at 11:31 PM, Jeremy <jbaino at gmail.com> wrote:
> Has there been any discussion about allocating the Class E blocks? If this
> doesn't count as "future use" what does? (Yes, I realize this doesn't *fix*
> the problem here)
> -Jeremy
> On Mon, Jan 31, 2011 at 10:15 PM, Jack Carrozzo <jack at crepinc.com> wrote:
>> On Mon, Jan 31, 2011 at 9:55 PM, Jimmy Hess <mysidia at gmail.com> wrote:
>> >
>> > IPv4's not dead yet;  even the first  RIR exhaustion probable in  3 -
>> > 6 months  doesn't end the IPv4 ride.
>> >
>> > There is some hope more IPv4 organizations will start thinking about
>> > their plans for establishing connectivity with IPv6;  so they can
>> > commmunicate with IPv6-only hosts that will begin to emerge
>> > later.
>> >
>> What organizations (eye networks) will do is layer NAT till the cows come
>> home for some years to come. Buckle up!
>> -Jack Carrozzo

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