IETF Logo Mail Archive

[IPv6]Re: New draft: "The IPv6 Loopback Address Prefix"

Ole Trøan <otroan.ietf@gmail.com> Wed, 03 December 2025 07:26 UTC

Return-Path: <otroan.ietf@gmail.com>
X-Original-To: ipv6@mail2.ietf.org
Delivered-To: ipv6@mail2.ietf.org
Received: from localhost (localhost [127.0.0.1]) by mail2.ietf.org (Postfix) with ESMTP id 0B88C9468643 for <ipv6@mail2.ietf.org>; Tue, 2 Dec 2025 23:26:41 -0800 (PST)
X-Virus-Scanned: amavisd-new at ietf.org
X-Spam-Flag: NO
X-Spam-Score: -2.099
X-Spam-Level:
X-Spam-Status: No, score=-2.099 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001] autolearn=ham autolearn_force=no
Authentication-Results: mail2.ietf.org (amavisd-new); dkim=pass (2048-bit key) header.d=gmail.com
Received: from mail2.ietf.org ([166.84.6.31]) by localhost (mail2.ietf.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id A4HYClfkgHF0 for <ipv6@mail2.ietf.org>; Tue, 2 Dec 2025 23:26:40 -0800 (PST)
Received: from mail-lf1-x12c.google.com (mail-lf1-x12c.google.com [IPv6:2a00:1450:4864:20::12c]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (P-256) server-digest SHA256) (No client certificate requested) by mail2.ietf.org (Postfix) with ESMTPS id A471A946863B for <ipv6@ietf.org>; Tue, 2 Dec 2025 23:26:40 -0800 (PST)
Received: by mail-lf1-x12c.google.com with SMTP id 2adb3069b0e04-5959187c5a9so5712244e87.1 for <ipv6@ietf.org>; Tue, 02 Dec 2025 23:26:40 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1764746799; x=1765351599; darn=ietf.org; h=to:in-reply-to:cc:references:message-id:date:subject:mime-version :from:content-transfer-encoding:from:to:cc:subject:date:message-id :reply-to; bh=hv+peGvlpubi75CccE79YU6IZdgKwu5T/62qI0Dddp4=; b=mDoKMgEPhh/E7CmIRNhdWrvk3/AsxYjkjwkk8E8WDVxBxi4ufClX+s6Y9xJqAXo9sU kc4DhYP88Zf2TAAUg/iwZ1xMb/C0f11BCm44aEGJT94/6OABjvdiY8IXgRHxY4squKwr ZZ1NZll3Bost8afZt6oV7ta67u4rrHy1BLZon37cZWBAPLH4euspla6X4+kPYr/BftQ5 fb6ya9HFHX0SN306+HG7300Tl/wcePjo/JCa3pE1iIDQdBfgYWJhmghynxjxtLkRSUBH eMV15lHK8U0RVHKCsaQMlALw7HcsZYgbWkHz9LcOU+cA2sK6v0mAs+NP7qBDeaF/qK6m frWw==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1764746799; x=1765351599; h=to:in-reply-to:cc:references:message-id:date:subject:mime-version :from:content-transfer-encoding:x-gm-gg:x-gm-message-state:from:to :cc:subject:date:message-id:reply-to; bh=hv+peGvlpubi75CccE79YU6IZdgKwu5T/62qI0Dddp4=; b=eKOOTJRAt3Vc/LN4IORDdLxQPXk40NM3bKGnWO/nXHmrLUdET4kULvOmOxj1nnvx7b ZXdLMQULZYV7Yx6BZIlhppZUb0CLXwN78amDh7wz8GNwzXFL+r8g9WM67w67jApEkmcC E4878JhiZ5DKGyDnAE0Oipf3WJ6BPTvzuhjmbOFe73qY2XXlT56RUYMnxB0YCLQS2FcZ t+kP8Sr5aKGJ2ch+MNtBn84BdkFBjtLd83202p2F38gglNAeEBJOVMxqOaE6kZNWSEKZ TPyGTIv0eIxGBcNBF24U+Ux9xx+z+PueKTpmcIhF/GKlFQikKW0gayMQ8LoatwpVrsAN ntDw==
X-Gm-Message-State: AOJu0Yze6YsnVNu4Vj1WNGCmTIgGrsg9bC0pqcJnHUnIwJsEirjBlF6S kY6AW68xdMMKimWwCMMimRBRZA0MdNoht/65MVcyUf9DJS1hXzwYZ2KnD5lQLQ==
X-Gm-Gg: ASbGncs4RXrI9Z44uxQuHSA/cinlk4KdAolCcuvud0pEMH6Beq4QZJx3sIL4ZE1v0Gp SbX0N7BMyBH0ojq5jRxVYY9+yoND4IQY6o2GWB7LFpJck1BP0sTqloVZ2vX+44RiH0yr/cbApId XQ+BEwgpgz6o9ehY+Qg8Dl9BEQaf9bAbZsOof9aS+7nhl5fxCClR5m+GnD2cnLa6Abe1l17LMpM kfpggEKgPOMm2mXadYNPpnSSrTxeXKpY+ehntV0Y7uZhhqdz9BB0WcLhIhnVOL5/RNbMd8Lvxlp zLif1QrzG2Ayla7TZM2mOjbZeDq6sQ16VB+kAT8EdUsJBglirgT57TOdlZk9ffrm4hIuhLkAcIy ZXUziLyJIe0sVgh9+AWhoL0Xa3drItkVGxV1GdjzXWAuI7fBTxt4TM2vhSL4GvjoXcDFqnovFAC Wox9G+rq9+ywa8I1QPo+B44aDBLMGt4DbRPQP6Kds1b6Y7
X-Google-Smtp-Source: AGHT+IEQ08ejahIpuDCAjFIn3Y10xciYp8aQpCbM+95x9q9DGAoawvs5meno0xxNqrwY3BjVla7q+w==
X-Received: by 2002:a05:6512:1195:b0:595:7a6c:7db4 with SMTP id 2adb3069b0e04-597d3f00ff9mr535952e87.4.1764746798632; Tue, 02 Dec 2025 23:26:38 -0800 (PST)
Received: from smtpclient.apple ([2001:4650:c3ed:37a:9e2a:f334:61dc:ff10]) by smtp.gmail.com with ESMTPSA id 2adb3069b0e04-596bfa49044sm5233279e87.87.2025.12.02.23.26.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 02 Dec 2025 23:26:37 -0800 (PST)
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: quoted-printable
From: Ole Trøan <otroan.ietf@gmail.com>
Mime-Version: 1.0 (1.0)
Date: Wed, 03 Dec 2025 08:26:25 +0100
Message-Id: <4DE60F08-5883-47A9-B094-659B7DD7D2B2@gmail.com>
References: <b335f5e9-b5df-4db0-a534-8c12d332b445@gmail.com>
In-Reply-To: <b335f5e9-b5df-4db0-a534-8c12d332b445@gmail.com>
To: Brian E Carpenter <brian.e.carpenter@gmail.com>
X-Mailer: iPhone Mail (23B85)
Message-ID-Hash: XJZ54BMJACQSIG72SLGMCAWDSV57RGSG
X-Message-ID-Hash: XJZ54BMJACQSIG72SLGMCAWDSV57RGSG
X-MailFrom: otroan.ietf@gmail.com
X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; header-match-ipv6.ietf.org-0; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header
CC: ipv6@ietf.org
X-Mailman-Version: 3.3.9rc6
Precedence: list
Subject: [IPv6]Re: New draft: "The IPv6 Loopback Address Prefix"
List-Id: "IPv6 Maintenance Working Group (6man)" <ipv6.ietf.org>
Archived-At: <https://mailarchive.ietf.org/arch/msg/ipv6/Xr9DBZbglH7_N-O1hnf36h6odg4>
List-Archive: <https://mailarchive.ietf.org/arch/browse/ipv6>
List-Help: <mailto:ipv6-request@ietf.org?subject=help>
List-Owner: <mailto:ipv6-owner@ietf.org>
List-Post: <mailto:ipv6@ietf.org>
List-Subscribe: <mailto:ipv6-join@ietf.org>
List-Unsubscribe: <mailto:ipv6-leave@ietf.org>

Brian,

> On 3 Dec 2025, at 07:59, Brian E Carpenter <brian.e.carpenter@gmail.com> wrote:
> 
> I don't think so. I think Bob's argument is just another version of "almost any address range would work for this purpose; it doesn't have to be special."

Doesn’t that depend on how we define loopback prefix behavior? I could not find that specified in either of the drafts. 

The current loopback address is automatically plumbed into existing implementations. 
- any traffic destined to the loopback address will be sent to the node itself (ie up the host stack). Is that the behavior proposed for the loopback prefix? Without any address configuration any packet with a DA of loopback prefix is sent up the host stack?
- routers do not forward any packets with a loopback source. This is hard coded in forwarding paths. 

How do the proponents of this idea intend for this to work? The suggestions of using an arbitrary prefix seems to imply people think no implementation changes are needed??

Cheers,
Ole

v2.39.1 | Report a Bug | By Email | System Status