IID length text [was Re: Review of draft-ietf-6man-rfc4291bis-06]

Brian E Carpenter <brian.e.carpenter@gmail.com> Sat, 14 January 2017 19:49 UTC

Return-Path: <brian.e.carpenter@gmail.com>
X-Original-To: ipv6@ietfa.amsl.com
Delivered-To: ipv6@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 13296129421 for <ipv6@ietfa.amsl.com>; Sat, 14 Jan 2017 11:49:44 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.7
X-Spam-Level:
X-Spam-Status: No, score=-2.7 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_LOW=-0.7, SPF_PASS=-0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=gmail.com
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 7BORd5N6LqBU for <ipv6@ietfa.amsl.com>; Sat, 14 Jan 2017 11:49:42 -0800 (PST)
Received: from mail-pf0-x231.google.com (mail-pf0-x231.google.com [IPv6:2607:f8b0:400e:c00::231]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id A5F171293DC for <ipv6@ietf.org>; Sat, 14 Jan 2017 11:49:42 -0800 (PST)
Received: by mail-pf0-x231.google.com with SMTP id f144so42994590pfa.2 for <ipv6@ietf.org>; Sat, 14 Jan 2017 11:49:42 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:references:from:organization:message-id:date:user-agent :mime-version:in-reply-to:content-transfer-encoding; bh=8bSnxapzg3EQI26ubZlie0A/es01iMVO26PDLuyKmQQ=; b=DRE/3exeXjo7xEmEYvvMN+Mmm40N0vYL4uiE2gt5Uu8sGkbMTcXoV4TlN88te8NMBi TFXbVFFL7lNKUmM8VMVpxIU2wJac0HcwkVWnSmPowuIV5StQ4W2xfWG8uLKrLanVuyal ypIr6nNaKqjnawNyyTrVJRCxvZ3lcy9TsppHofzeYE7ZWRd/M8io5NmzJuzIE8gxH7ry B6sOq4Z0iJ7UCMflbCq71ydWbZPszUhhAcKPvTm47siZQgXfMwpHN2TyaHMk3ZU4BrFJ aDaW1Lu2OJd3005T7IAWfCLuR1ksV0hPNIR3K5pKEMkDxnCuRlZ6DptsbQDPZyI41T22 DS1Q==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:organization :message-id:date:user-agent:mime-version:in-reply-to :content-transfer-encoding; bh=8bSnxapzg3EQI26ubZlie0A/es01iMVO26PDLuyKmQQ=; b=Oew7TlfrUeoy2EZ0gj5uhUjPwZDBcDyAE5laOjIXddw4yWHx93S/4VdDZm46rqtK53 +zE53bHlvY+q1f2KHSko8Ecdt5C2+e/+7q2bO+ZwgwsNxk52hh6Eo1EAouVWl8aduN6h c3Q19JBYCcqrYdVlr4t2+zVDYJgd6ripnBXCggWASauZ0finnUFFrBiOvlBuD+EufJil 2U0KHLiVt8fklAnJSa/x7GbnpM6RjzkDh5JICtQdMdfY2g/qqxQVSiH4AJAFVyOwaMMc SUS5SLGFmugmOXQU2+NKWo9eDNN11cvcXNKtyrR94P5s5vY6NSZhb3fQyqAK2VMa7G00 FAaQ==
X-Gm-Message-State: AIkVDXJDKs9dGIxOC3/LEROFBwYwZ8Q4nGQotzl6Zf3fYMwsPoacagnDJ+MllH/BFaL67Q==
X-Received: by 10.98.160.89 with SMTP id r86mr17093576pfe.170.1484423382148; Sat, 14 Jan 2017 11:49:42 -0800 (PST)
Received: from [192.168.178.21] ([118.149.103.96]) by smtp.gmail.com with ESMTPSA id z66sm13024389pfd.49.2017.01.14.11.49.40 for <ipv6@ietf.org> (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 14 Jan 2017 11:49:41 -0800 (PST)
Subject: IID length text [was Re: Review of draft-ietf-6man-rfc4291bis-06]
To: 6man <ipv6@ietf.org>
References: <148406593094.22166.2894840062954191477.idtracker@ietfa.amsl.com> <m2fukqbbwv.wl-randy@psg.com> <F6953234-3F85-4E28-9861-433ADD01A490@gmail.com> <m2wpdzhncn.wl-randy@psg.com> <82245ef2-cd34-9bd6-c04e-f262e285f983@gmail.com> <m2d1frhjfn.wl-randy@psg.com> <18e6e13c-e605-48ff-4906-2d5531624d64@gmail.com> <CAKD1Yr1cvZ8Y3+bHeML=Xwqr+YgDspZGnZi=jqQj4qe2kMc4zw@mail.gmail.com> <m2lguffnco.wl-randy@psg.com> <CAKD1Yr1TrTiPRdyutobmb_77XJ7guNzLrg=H_p7qi4BfQ8V=GA@mail.gmail.com> <m2d1frfm6m.wl-randy@psg.com> <CAKD1Yr2Njjd8_Mr+6TRFF6C5pdcX4yFgpFVyEkykDuytu2B8mg@mail.gmail.com> <2A5073777007277764473D78@PSB> <4596c3d4-a337-f08e-7909-f14270b7085f@gmail.com> <CAN-Dau06R3iYRpYLADhvHox4C9qdsJCuxFsJapRhOQcWT4qk_g@mail.gmail.com> <CAO42Z2weZcoHiBzN94QAQ9WGhWR16PmMMFNg=5YLmr_dhPjjpA@mail.gmail.com>
From: Brian E Carpenter <brian.e.carpenter@gmail.com>
Organization: University of Auckland
Message-ID: <fcf580ec-3617-ca5f-5337-37acb6e928ba@gmail.com>
Date: Sun, 15 Jan 2017 08:49:37 +1300
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.6.0
MIME-Version: 1.0
In-Reply-To: <CAO42Z2weZcoHiBzN94QAQ9WGhWR16PmMMFNg=5YLmr_dhPjjpA@mail.gmail.com>
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit
Archived-At: <https://mailarchive.ietf.org/arch/msg/ipv6/YYVhDE9xt4kHAm6ODyedQOUiHn8>
X-BeenThere: ipv6@ietf.org
X-Mailman-Version: 2.1.17
Precedence: list
List-Id: "IPv6 Maintenance Working Group \(6man\)" <ipv6.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/ipv6>, <mailto:ipv6-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/ipv6/>
List-Post: <mailto:ipv6@ietf.org>
List-Help: <mailto:ipv6-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ipv6>, <mailto:ipv6-request@ietf.org?subject=subscribe>
X-List-Received-Date: Sat, 14 Jan 2017 19:49:44 -0000

A modest suggestion:

OLD
   For all unicast addresses, except those that start with the binary
   value 000, Interface IDs are required to be 64 bits long.  Background
   on the 64 bit boundary in IPv6 addresses can be found in [RFC7421].

NEW
   IPv6 routing is based on prefixes of any valid length up to 128 [BCP198].
   For example, [RFC6164] standardises 127 bit  prefixes on point-to-point
   links. However, consistent use of Stateless Address Autoconfiguration
   (SLAAC)[RFC4862] requires that all interfaces on a link use the same length
   of Interface ID. In practice, this means that to guarantee interoperability
   of SLAAC, a fixed length of Interface ID is necessary. For all currently
   allocated unicast addresses, except those that start with the binary
   value 000, that length is 64 bits. Note that this value is an arbitrary
   choice and might be changed for some future allocation of unicast address
   space. Background on the 64 bit boundary in IPv6 addresses can be found
   in [RFC7421].

Regards
   Brian