Re: Non routable IPv6 registry proposal

Masataka Ohta <> Thu, 21 January 2021 11:58 UTC

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Subject: Re: Non routable IPv6 registry proposal
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From: Masataka Ohta <>
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Date: Thu, 21 Jan 2021 20:57:59 +0900
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Phillip Hallam-Baker wrote:

> First off, before I start, can I please ask that nobody respond with 'that
> is stupid, that is not how it works'.

Not stupid.

Your point that NAT is fine is not stupid but it means IPv4 with
NAT is fine obsoleting IPv6, which, though, makes your proposal
insisting on IPv6 meaningless.

> 0) Nowhere does the 'end to end' principle demand that the source and
> destination addresses on an IP packet remain constant.

Correct. As long as both ends can restore the original IP addresses,
modifying them between the ends is fine.


for details.

> 2) NAT multiplexing will become an increasing problem

> As people end up with thousands of devices inside their home, port
> exhaustion at the NAT box and the ridiculous complexity of it all is going
> to become a major headache.

Feel free to pay more to your ISP if you want to enjoy using more ports
of an address, just as when you want to enjoy more addresses.

> 3) 10.x.x.x is not enough

For private use, I don't think so.

> Solution
> The solution is to provide a non-routable space where address block
> collisions are unlikely. Each enterprise that uses this space is assured
> that the probability of collisions is small. This can also be used within
> existing enterprises to regularlize mapping of the typical horrorshow of
> hundreds of overlapping 10.x.x.x etc. spaces onto a different private range.

You are saying 24bit address range of 10.x.x.x is enough for all the
large organizations have unique addresses.

Then, x.x.x.x should be enough for all the people and organizations
have unique addresses, which is obviously wrong.

						Masataka Ohta