Re: [v6ops] Scope of Unique Local IPv6 Unicast Addresses (Fwd: New Version Notification for draft-gont-6man-ipv6-ula-scope-00.txt)

Christopher Morrow <christopher.morrow@gmail.com> Wed, 06 January 2021 07:30 UTC

Return-Path: <christopher.morrow@gmail.com>
X-Original-To: v6ops@ietfa.amsl.com
Delivered-To: v6ops@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id B63C83A11C2; Tue, 5 Jan 2021 23:30:45 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.098
X-Spam-Level:
X-Spam-Status: No, score=-2.098 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, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=unavailable 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 hLA3otnRg3Hl; Tue, 5 Jan 2021 23:30:43 -0800 (PST)
Received: from mail-qt1-x82a.google.com (mail-qt1-x82a.google.com [IPv6:2607:f8b0:4864:20::82a]) (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 B052B3A11BE; Tue, 5 Jan 2021 23:30:43 -0800 (PST)
Received: by mail-qt1-x82a.google.com with SMTP id c14so1579942qtn.0; Tue, 05 Jan 2021 23:30:43 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=B09ywsGA62ENIR/fCzCVsO5C/xl/SVDxSOe5Op63kOM=; b=ek75tAkOEp1cEBeq53fFrxWr9c071vLaQoToXCIAhBTuCmFeqDcBUyYb2ir2ByXVun ud7glL3nWg9Zr0HFZeAej8ceLBhGh2PI3gMZqWzeKiMaGrF7Nxv7Tq2NHVJBOLrxa+yJ kS/yoymsUi2zmwUK+OEBqjRAOamJWi8f0m9+G/f8FDyowWJCJwtGEx+/BzH1NndVGThp LtdKpeh469NmumxnKkGH/RiSiVq5kLxJX4i/W4iI7EccGy3ptDrVKgkNNIPsa71paAqs mAooYzwzw3r90p2Nrhoh+r6qLkPVUQGqreNMZxATASSP0hndY7QcP8pNNJ4u/e4xV3Zu vLUw==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=B09ywsGA62ENIR/fCzCVsO5C/xl/SVDxSOe5Op63kOM=; b=fZZR+/mEQfx5lQsCTaAnUM7PoFi6tIHTNJbkjGd0geuTLwdyGSlw+tNVdVb5EPRzgB Q3NnpwP2Ia8tVbThKHLud3QDZ2u6aCKN6t/ejqiePofsy7iD/ikajQgC3SM/s1qmSYdG WIXwjOUMEG3C9eJwf74sf4CpBnmz7XLIFfV7zHFodohe5gVAMnLDI8G4jb2qri3SiRMn AVn1AQlq1SAKmLuH25DNl+hzMTHnBMKeoMriJvTyeXXSoifwmMVmqe1w+8X+nkdlj/Z6 ol3/FsJFQ5X2JYl4BGTXxyP+gG428WDqRp9l+S7LM8WCseeysUEOKT+JPKx73WPDYWoJ w0fA==
X-Gm-Message-State: AOAM530Ji3DjkUh1t6flZNoYnJtfF3JpHThulmMzMW3O4/m94EmCndaI cSRO38SnB49SNTTBWKt96XFfH25Z4E3BmfPBagM=
X-Google-Smtp-Source: ABdhPJzwDFeCmWmM9ZD7yWv4vgyfvQZotdId8kM9jYQduV27QvVKSUQ2RILMrf7FlNgdOh1LMctQ3lOiYNdv/dcVgWc=
X-Received: by 2002:aed:2e63:: with SMTP id j90mr3043667qtd.338.1609918242587; Tue, 05 Jan 2021 23:30:42 -0800 (PST)
MIME-Version: 1.0
References: <160989494094.6024.7402128068704112703@ietfa.amsl.com> <6fe3a45e-de65-9f88-808d-ea7e2abdcd16@si6networks.com> <CAO42Z2wR-3vbHi-NrBBMmCTNDq5fgqvSmBUbYK7P+63QTNfxkg@mail.gmail.com> <CAKD1Yr014PzVJj9Y6O=PBGc_QSVtur-0wMpaNkFA0dqr8FHGuA@mail.gmail.com>
In-Reply-To: <CAKD1Yr014PzVJj9Y6O=PBGc_QSVtur-0wMpaNkFA0dqr8FHGuA@mail.gmail.com>
From: Christopher Morrow <christopher.morrow@gmail.com>
Date: Wed, 6 Jan 2021 02:30:31 -0500
Message-ID: <CAL9jLaZA4y+9bdvzq5r4V=B6580ZnsdwYyvQ4nzjdeccMsM4Tg@mail.gmail.com>
To: Lorenzo Colitti <lorenzo=40google.com@dmarc.ietf.org>
Cc: Mark Smith <markzzzsmith@gmail.com>, Fernando Gont <fgont@si6networks.com>, IPv6 Operations <v6ops@ietf.org>, 6MAN <6man@ietf.org>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Archived-At: <https://mailarchive.ietf.org/arch/msg/v6ops/Sh0wNAPMITuuYAqzAoDn8Ub0HfU>
Subject: Re: [v6ops] Scope of Unique Local IPv6 Unicast Addresses (Fwd: New Version Notification for draft-gont-6man-ipv6-ula-scope-00.txt)
X-BeenThere: v6ops@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: v6ops discussion list <v6ops.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/v6ops>, <mailto:v6ops-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/v6ops/>
List-Post: <mailto:v6ops@ietf.org>
List-Help: <mailto:v6ops-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/v6ops>, <mailto:v6ops-request@ietf.org?subject=subscribe>
X-List-Received-Date: Wed, 06 Jan 2021 07:30:46 -0000

On Wed, Jan 6, 2021 at 2:09 AM Lorenzo Colitti
<lorenzo=40google.com@dmarc.ietf.org> wrote:
>
> On Wed, Jan 6, 2021 at 11:01 AM Mark Smith <markzzzsmith@gmail.com> wrote:
>>
>> ULAs are intended to be globally unique addresses, but not to be globally (Internet) forwardable. Their forwarding scope is limited to non-global, either within a single local network, or between a set of local networks that have agreed to forward their respective ULA /48 prefixes between each other, overriding the default of local networks only forwarding scope. (Ethernet addresses are a similar example, globally unique addresses, link only forwarding scope.)
>
>
> IMO defining ULAs as they are was a mistake. Global scope implies unique. But probabilistic uniqueness doesn't work because humans choose ULAs instead of generating them manually. Registry-based uniqueness doesn't work (and, to be fair, was never tried by the IETF) because there is no registry that has jurisdiction. Even if there were, there is no reason to keep addresses unique if they don't have global reachability.
>
> So I guess I'm somewhere between 1) and 3). The specs are consistent but they fail to consider human behaviour, so they don't actually work in practice. I don't know what to do about this though. If we say they're non-global scope, then they are going to be the exact equivalent of RFC1918 addresses, with all the problems that that causes. If we continue to say they're global scope, then the specs don't match reality. :-(

option 4, deprecate ULA.
the best option (tm).