Re: IPv6 only host NAT64 requirements?

Lee Howard <> Mon, 20 November 2017 21:05 UTC

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Date: Mon, 20 Nov 2017 16:05:19 +0800
Subject: Re: IPv6 only host NAT64 requirements?
From: Lee Howard <>
To: "Manfredi, Albert E" <>, Brian E Carpenter <>
CC: 6man WG <>
Message-ID: <>
Thread-Topic: IPv6 only host NAT64 requirements?
References: <> <> <> <> <787AE7BB302AE849A7480A190F8B93300A07AD68@OPEXCLILMA3.corporate.adroot.infra.ftgroup> <> <787AE7BB302AE849A7480A190F8B93300A07C625@OPEXCLILMA3.corporate.adroot.infra.ftgroup> <> <787AE7BB302AE849A7480A190F8B93300A07D481@OPEXCLILMA3.corporate.adroot.infra.ftgroup> <> <787AE7BB302AE849A7480A190F8B93300A07D534@OPEXCLILMA3.corporate.adroot.infra.ftgroup> <> <787AE7BB302AE849A7480A190F8B93300A07D63D@OPEXCLILMA3.corporate.adroot.infra.ftgroup> <> <> <>
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On 11/21/17, 4:12 AM, "ipv6 on behalf of Manfredi, Albert E"
< on behalf of> wrote:

>-----Original Message-----
>From: ipv6 [] On Behalf Of Brian E Carpenter
>> However, as long as even one application, such as one VPN, or one
>> literal IPv4 address, fails, that represents millions of failure
>> cases if we consider the whole world (e.g. imagine every hotel
>> network in the world running IPv6+NAT64 only).
>Very instructive thread for me, I must say. I'm getting this sense of
>urgency, to be rid of IPv4, but it comes from the IETF 6man wg and some
>ISPs. Ultimately, it's not up to 6man to decide. It's up to device
>vendors, and up to the deployed base of devices. The IETF can only
>suggest, and ISP networks have to meet the real world needs.

It’s a multi-legged stool, where network operators, device vendors, and
content all have a role, and will make their own operational decisions.
Operators may decide not to support IPv4-only devices or applications, or
to charge more for them, or to provide translators. Device makers may
decide to support dual-stack, or CLAT, or IPv6-only, or IPv4-only. Etc.

>> Dual stack in every hotel room in the world is viable, from the
>> hotel guests' point of view.
>This seems the most practical answer, whether it's a client server model,
>such as in a hotel room, or a peer to peer network. In a mostly peer to
>peer network, the normal case would be for IPv6 hosts to be introduced
>gradually. I'm not sure how anything other than dual stack can work, in
>this case. If the goal is to have continuous robust operation of the
>network, during an indefinitely long transitional phase, because no one
>up the chain could care less about the nitty gritty, they just want
>everything to keep working flawlessly, then what motivation would there
>be for anything other than dual stack?

IPv4 addresses selling for US$15 each and rising? At what price do
operators stop doing native dual stack?

> The only practical solution is to introduce IPv6 hosts only if they are
>dual stack. And then carefully, on a case by case basis, individual
>subsystems that do not need to interoperate with IPv4 subsystems can shut
>off IPv4.

It’s too late for dual-stack to be the transition plan.

>I realize that such transition drag on for years. But again, in the
>greater scheme of things, this matters very little to those who must make
>sure the systems work at all times.

Yes, years.
Five years until 90% of hosts have IPv6. It’s going to be a bumpy few
years, especially for those who insist IPv6 is somebody else’s problem.