As I understand the initial question: the client has no IPv4.

Initial “4” in 464XLAT means IPv4 client.

DNS64 could mislead the client that the server (on the internet) is available on IPv6.

Then NAT64 would convert IPv6 to IPv4.

But it is not stateless by any means (requested below).

Ed/

From: Ca By [mailto:cb.list6@gmail.com]
Sent: Monday, October 10, 2022 7:27 PM
To: Vasilenko Eduard <vasilenko.eduard@huawei.com>
Cc: Carlos Martinez-Cagnazzo <carlosm3011@gmail.com>; NANOG <nanog@nanog.org>
Subject: Re: Any experiences using SIIT-DC in an IXP setting ?

On Mon, Oct 10, 2022 at 9:17 AM Vasilenko Eduard via NANOG <nanog@nanog.org> wrote:

The technology for IPv6 client to connect IPv4 web server on Internet is just not specified in IETF.

Ed/

Ed, you seem to be not so familiar with the this ietf body of work

RFC6877 

“ 464XLAT is a simple and scalable

   technique to quickly deploy limited IPv4 access service to IPv6-only
   edge networks without encapsulation.

”

To the OP, you can google jpix has done this. 

From: NANOG [mailto:nanog-bounces+vasilenko.eduard=huawei.com@nanog.org] On Behalf Of Carlos Martinez-Cagnazzo

Sent: Monday, October 10, 2022 6:57 PM
To: NANOG <nanog@nanog.org>
Subject: Any experiences using SIIT-DC in an IXP setting ?

Hi all,

I'm looking at a use case for stateless 6-4 mappings in the context of an IXP.

The problem we are looking to solve is allowing IXP members who have no IPv4 of their own and in most cases they have a /26 or /27 issued by their transit provider and rely on CGN to provide service to their customers. They do have their own AS numbers and IPv6 prefixes though.

Any comments are appreciated. PM is fine too.

Thanks!

/Carlos