Re: [Idr] Erik Kline's Discuss on draft-ietf-idr-tunnel-encaps-20: (with DISCUSS and COMMENT)

Erik Kline <ek.ietf@gmail.com> Tue, 01 December 2020 05:47 UTC

Return-Path: <ek.ietf@gmail.com>
X-Original-To: idr@ietfa.amsl.com
Delivered-To: idr@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 944603A0A42; Mon, 30 Nov 2020 21:47:06 -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=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 n_jBbb0GwvzE; Mon, 30 Nov 2020 21:47:05 -0800 (PST)
Received: from mail-ot1-x334.google.com (mail-ot1-x334.google.com [IPv6:2607:f8b0:4864:20::334]) (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 A34B93A0A35; Mon, 30 Nov 2020 21:47:04 -0800 (PST)
Received: by mail-ot1-x334.google.com with SMTP id f16so572772otl.11; Mon, 30 Nov 2020 21:47:04 -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; bh=OCtt3hED3LmmEJVB9vmWLaGv79n2qeBGpQ6Vb4auxRw=; b=nzVulI1gQqchHNX3nYeZ/9Ydgrwx9WpuQ4TFMS0RNkOddPnJEmeyzjcCpVVtOlTC9x bxZ36ZV5bEhzmLraw6Ju7oSHTfc8k/SDBNmuZk5+ldZ3riUOGpBpvcN50izXfNlFR0ZF wSYL5Ur+GAPxWkYY4ALVGz5Jqxfyhr/FPH0hHGlmAX3LTMh0urDeeeoi9jv0IOsG+pjf CmY978Fw8Mt4p7DCitABUk5/0el0UU7fNdS6fzNNzrCslvmF7YEF708Ia67RYyBQpqc5 IQB2QVH6gQ2Ge+p4qfZhBXQVaKxx8J01k/Ib3RZrx3f9OarKiatJZJupVlk6e6B3SNf2 PeOg==
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; bh=OCtt3hED3LmmEJVB9vmWLaGv79n2qeBGpQ6Vb4auxRw=; b=qLUVL66Agtm9BQlBDAZ6KiJJ1baLAaeafORa97w8Za7ybKusLq5Np0R9FiAXVQL9kZ B7jrklxxsGjPgP59KL6hOxfVRyn2pHXUBMQsI7W8pPQc50BUjaiGeN9x5Ks1tXLwFmdP 8lplEmb7v0Pa4KXgISwAlZqt5Eefz9cxbIX1v7IEyKm8yyZtdaKYY30/5kJWnXlV1OPb E4TLfsovPs8CpqBxKvZIvbxJi7TpTY9WAWYe69CYHnQgwMx0rSufTIman7BX5MaA3Vqk rcBqpcXzn3j027VgDqGy5K92z5VRNMjbO0XakCMqm/2beiqnyqwsDfZd+YJOAzLpsxT3 xaIA==
X-Gm-Message-State: AOAM532okYhKnCEwuh8P89GTpkNYWTOFU1e6F7wuLFbxGaejTIrVoQyd DpTLKy6csSRxPtoTr4feNU89ExXPlZ5/eRirbVM=
X-Google-Smtp-Source: ABdhPJxlI6dNO2O2z2R3Agg8D75c3eRjRsdhv0+UJLu1raEaKLpVbcyaRBxcStBRFL29T898plyHQ7iuzpENyE6I1B0=
X-Received: by 2002:a9d:69d3:: with SMTP id v19mr845544oto.155.1606801623688; Mon, 30 Nov 2020 21:47:03 -0800 (PST)
MIME-Version: 1.0
References: <160680054195.20603.3437170887601694105@ietfa.amsl.com>
In-Reply-To: <160680054195.20603.3437170887601694105@ietfa.amsl.com>
From: Erik Kline <ek.ietf@gmail.com>
Date: Mon, 30 Nov 2020 21:46:53 -0800
Message-ID: <CAMGpriWGH4tcA++8jgTgO47T2MdhZcsAdYP5_PuuYr+U2t9C_g@mail.gmail.com>
To: Erik Kline <ek.ietf@gmail.com>
Cc: The IESG <iesg@ietf.org>, "idr@ietf. org" <idr@ietf.org>, idr-chairs@ietf.org, Alvaro Retana <aretana.ietf@gmail.com>, John Scudder <jgs@juniper.net>, draft-ietf-idr-tunnel-encaps@ietf.org, shares@ndzh.com
Content-Type: text/plain; charset="UTF-8"
Archived-At: <https://mailarchive.ietf.org/arch/msg/idr/x1kYgDZe5xbeMW5wwYq4qTudakQ>
Subject: Re: [Idr] Erik Kline's Discuss on draft-ietf-idr-tunnel-encaps-20: (with DISCUSS and COMMENT)
X-BeenThere: idr@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Inter-Domain Routing <idr.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/idr>, <mailto:idr-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/idr/>
List-Post: <mailto:idr@ietf.org>
List-Help: <mailto:idr-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/idr>, <mailto:idr-request@ietf.org?subject=subscribe>
X-List-Received-Date: Tue, 01 Dec 2020 05:47:07 -0000

On Mon, Nov 30, 2020 at 9:29 PM Erik Kline via Datatracker
<noreply@ietf.org> wrote:
>
> Erik Kline has entered the following ballot position for
> draft-ietf-idr-tunnel-encaps-20: Discuss
>
> When responding, please keep the subject line intact and reply to all
> email addresses included in the To and CC lines. (Feel free to cut this
> introductory paragraph, however.)
>
>
> Please refer to https://www.ietf.org/iesg/statement/discuss-criteria.html
> for more information about IESG DISCUSS and COMMENT positions.
>
>
> The document, along with other ballot positions, can be found here:
> https://datatracker.ietf.org/doc/draft-ietf-idr-tunnel-encaps/
>
>
>
> ----------------------------------------------------------------------
> DISCUSS:
> ----------------------------------------------------------------------
>
> [ section 3.3.1 ]
>
> * The text about "[a]ny one-octet value can be transported" leaves me
>   wondering about how values that result in ECN bits being set should be
>   treated.
>
>   I think there needs to be some recognition here that the DSCP part of
>   the octet is only 6 bits (2474 section 3), and that bits 6 & 7 "MUST/SHOULD
>   be zero on transmission and MUST/SHOULD be ignored by the recipient".
>
>   Another way to ask the question here is: if ECN is not to be specified as
>   part of this octet (and IMHO it should not be), which ranges of 6 bit
>   values are permitted: [0..63], with the understanding this will be shifted
>   before setting the octet, or [0,4,8,12,...,252]?  Given the text "It
>   specifies the setting of the one-octet...", I think it implies the latter,
>   but some clarification would, I think, be helpful.

If the argument is essentially: this is the value to stuff into
something like setsockopt(..., IP_TOS|IPV6_TCLASS, ...) which (in
Linux) accept an 8 bit value as is, then suppose that makes sense.

> ----------------------------------------------------------------------
> COMMENT:
> ----------------------------------------------------------------------
>
> [[ questions ]]
>
> [ section 3.1 ]
>
> * The prohibition against use of Forwardable=false egress IPs I think means
>   that IPv4 and IPv6 link-local addresses cannot be used.  It seems somewhat
>   unusual, but not completely outside the realm of reasonable, to have a
>   situation where two on-link routers could be configured by their respective
>   administrators to use some encapsulation for forwarded packets without
>   having to resort to global unicast addresses.
>
>   Are we sure this (odd) use case should be prohibited?
>
>   The final paragraph of this section seems to cover the use of non-reachable
>   addresses just fine.  Obviously link-local IPs would need to be exempt from
>   section 3.1.1 AS-owned address validation.
>
> [ section 3.3+ ]
>
> * Do any implementations wish to set IPv6 flow labels?
>
> [ section 6 ]
>
> * Might MTU overhead a consideration in tunnel selection?  I.e., given more
>   than one tunnel option might an implementation choose based on minimizing
>   total overhead?
>
>
>