This document directs the IANA to designate the block of IPv4
addresses from 240.0.0.0 to 255.255.255.255
(240.0.0.0/4) as unicast
address space for limited use in large private Internets.
Some widespread IPv4 stacks refuse to handle these addresses,
so nobody would ever want to use them on the public IPv4 Internet.
And some widespread IPv4 stacks, refuse to handle IPv6 addresses. I guess that
means we should deprecate IPv6? Or should we merely update the software?
In any case, the most worrying aspect of this is the number fo /8's that are
proposed to be handed over for private use at a time when we are running short
of IPv4 addresses. I would think that two /8s is more than enough.
Assuming that these private users manage to resolve the technical issues of
using former class E addresses, and get some vendors to update their
software/firmware, then the rest of the /8's should be handed over to the RIRs
for general use (with caveats). In much the same way as an applicant for an AS
number can now specify that they will accept a 4-byte Asnum, these former class
E addresses could be handed out to those who will accept it.
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