X-Recipient: archive-cygwin AT delorie DOT com
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 301863858C50
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cygwin.com;
	s=default; t=1700544954;
	bh=6MgJMDOFvN3VAi1JUvbyfWHrEr64CMVM9wPAznU64jM=;
	h=Date:Subject:To:References:In-Reply-To:List-Id:List-Unsubscribe:
	 List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc:
	 From;
	b=YNTXzNOvFLnkfN5UB15vsJsUEEdbIR4wtxgmaVXwPRnh/r9mzlFubkij3oOU2ASaN
	 RRRTqvmx04L7+/lAJVOllGeYBhb/hVHyGu5BkUdWYVah1edyE/XNrvLHeTtvxxPITP
	 SnOKk2ueZaDHpj3gfoLW59uGy3V40P5kMw/X3Hwk=
X-Original-To: cygwin AT cygwin DOT com
Delivered-To: cygwin AT cygwin DOT com
DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 251F53858D35
ARC-Filter: OpenARC Filter v1.0.0 sourceware.org 251F53858D35
ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1700544941; cv=none;
 b=lIKLyOk+IGh3is6qDeavEq9EWY7HvgdhTj9udT1dsJLBlhZlY6VL8MedULzoto0zC3KUGAUr5/76DBIP3FWEmsvSCPpT32mTtB5iRmlGMvihLcNl+oHGUGPzymXzjaWhG8lQFXekHNukSLBLd+e0u4decHn9bf83VUvwWqxQ1Lo=
ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key;
 t=1700544941; c=relaxed/simple;
 bh=sx4FTL15Ymx1xDDlllUjxLjcvdEzLXS3Jgm2Ldn5CCY=;
 h=DKIM-Signature:Message-ID:Date:MIME-Version:Subject:To:From;
 b=rE31qcsLqHNeBMmPn3Ga6fiHysrh2+o6vGcX6fLJQiE3o6Nv/zBjndYQbeFRqtiOhFcG7uExgsc2F/4FLnFG0d5f4O1s0W+AFcUcYt5YsHO5Ip7U30YOxd3S8//gvyI932ZeksLOln22bBvpi3XzfC1ZrhyVgHuLW1HA7KLqVCo=
ARC-Authentication-Results: i=1; server2.sourceware.org
X-Authority-Analysis: v=2.4 cv=CZQbWZnl c=1 sm=1 tr=0 ts=655c41ab
 a=DxHlV3/gbUaP7LOF0QAmaA==:117 a=DxHlV3/gbUaP7LOF0QAmaA==:17
 a=IkcTkHD0fZMA:10 a=BqEg4_3jAAAA:8 a=EfKubs0AG1NhwE_uHWUA:9 a=QEXdDO2ut3YA:10
 a=0mFWnFbQd5xWBqmg7tTt:22
Message-ID: <db86fa40-991c-4977-9bff-668cb28fff93@Shaw.ca>
Date: Mon, 20 Nov 2023 22:35:38 -0700
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Subject: Re: Please support download setup-x86_64.exe on IPv6-only network
Content-Language: en-CA
To: cygwin AT cygwin DOT com
References: <CAMW-drsZiD6DawJV31kD4YMcxow+TB2VKLRqG7GOgjsxm2A5tw AT mail DOT gmail DOT com>
 <CANH4o6OM4oTJ0zWBdrx7X0PHX2Vj3EwiEmOtJ+i8JtpsXiOwKQ AT mail DOT gmail DOT com>
 <20231116101858 DOT vxbvtipwtvwucwjs AT lucy DOT dinwoodie DOT org>
 <635d3f94-f104-49e0-9248-1cace4da9fa6 AT Shaw DOT ca>
 <CAKwdsS_+gH+RuNwCC6h_eDcF5m_Ov2DeqTyUhbS43CTHvEEptA AT mail DOT gmail DOT com>
 <CAD8GWsuwdbydtG98DTZNrsmQ50Z1T7iwVs6dMx0E50qbCfCCcQ AT mail DOT gmail DOT com>
Organization: Inglis
In-Reply-To: <CAD8GWsuwdbydtG98DTZNrsmQ50Z1T7iwVs6dMx0E50qbCfCCcQ@mail.gmail.com>
X-CMAE-Envelope: MS4xfLDly0vMwpHn0X6DwVugt/II51KtQZRibSWUORN4cMohV5lnMf+t9hiitpImZpeMObkdAwwvC25pnjYYVmYPAgHnZyfPS4z2l3EZQXnwVJlQ+GD01mcs
 eGb0eb6AfGhbv6OrfYb30cTbUbkosyBm9N2XIIkcUpLk6v/INmkwBivHcNTb6XCR0YV5UyDD068Ppg==
X-Spam-Status: No, score=-3.3 required=5.0 tests=BAYES_00, DKIM_SIGNED,
 DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H3,
 RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, TXREP, T_SCC_BODY_TEXT_LINE,
 T_SPF_PERMERROR autolearn=ham autolearn_force=no version=3.4.6
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on
 server2.sourceware.org
X-BeenThere: cygwin AT cygwin DOT com
X-Mailman-Version: 2.1.30
Precedence: list
List-Id: General Cygwin discussions and problem reports <cygwin.cygwin.com>
List-Unsubscribe: <https://cygwin.com/mailman/options/cygwin>,
 <mailto:cygwin-request AT cygwin DOT com?subject=unsubscribe>
List-Archive: <https://cygwin.com/pipermail/cygwin/>
List-Post: <mailto:cygwin AT cygwin DOT com>
List-Help: <mailto:cygwin-request AT cygwin DOT com?subject=help>
List-Subscribe: <https://cygwin.com/mailman/listinfo/cygwin>,
 <mailto:cygwin-request AT cygwin DOT com?subject=subscribe>
From: Brian Inglis via Cygwin <cygwin AT cygwin DOT com>
Reply-To: cygwin AT cygwin DOT com
Cc: Brian Inglis <Brian DOT Inglis AT Shaw DOT ca>
Content-Type: text/plain; charset="utf-8"; Format="flowed"
Errors-To: cygwin-bounces+archive-cygwin=delorie DOT com AT cygwin DOT com
Sender: "Cygwin" <cygwin-bounces+archive-cygwin=delorie DOT com AT cygwin DOT com>
Content-Transfer-Encoding: 8bit
X-MIME-Autoconverted: from base64 to 8bit by delorie.com id 3AL5ZsNe019906

On 2023-11-20 17:45, Lee via Cygwin wrote:
> On Mon, Nov 20, 2023 at 7:13 PM Backwoods BC via Cygwin wrote:
>>
>> On Thu, Nov 16, 2023 at 12:41 PM Brian Inglis via Cygwin wrote:
>>> The whole IP v4 internet is available as a compatibility subnet ::ffff:0:a.b.c.d
>>> on IP v6, so there is no excuse for not supporting interconnection, as it will
>>> be required until the last backbone routers drop IP v4 support.
>>
>> Just a small correction for the mail archives as this appears solved.
>> The correct IPV6 address for the IPV4 address range is
>> ::ffff:a.b.c.d  (no '0')
> 
> If you're going for correcting the record, let's make it correct.
> ::ffff:a.b.c.d is not a solution for IPv6 => IPv4 interconnection over
> the Internet.
> 
> from:  https://www.rfc-editor.org/rfc/rfc5156
> 
> 2.2.  IPv4-Mapped Addresses
> 
>     ::FFFF:0:0/96 are the IPv4-mapped addresses [RFC4291].  Addresses
>     within this block should not appear on the public Internet.

These internal addresses are used by dual stack hosts to allow clients or 
servers to handle connections to IPv4 hosts the same as IPv6 hosts.

Whereas ::ffff:0:0:0/96 == ::ffff:0:a.b.c.d allows IPv6 only hosts without 
assigned IPv4 addresses to connect to IPv4 only hosts via SIIT see:

	https://www.rfc-editor.org/rfc/rfc7915 Stateless IP/ICMP Translation.

-- 
Take care. Thanks, Brian Inglis              Calgary, Alberta, Canada

La perfection est atteinte                   Perfection is achieved
non pas lorsqu'il n'y a plus rien à ajouter  not when there is no more to add
mais lorsqu'il n'y a plus rien à retirer     but when there is no more to cut
                                 -- Antoine de Saint-Exupéry

-- 
Problem reports:      https://cygwin.com/problems.html
FAQ:                  https://cygwin.com/faq/
Documentation:        https://cygwin.com/docs.html
Unsubscribe info:     https://cygwin.com/ml/#unsubscribe-simple