Re: [spring] Penultimate Segment Popping and RFC8200 (Was Re: We don't seem to be following our processes (Re: Network Programming - Penultimate Segment Popping))

Robert Raszuk <robert@raszuk.net> Wed, 11 December 2019 20:32 UTC

Return-Path: <robert@raszuk.net>
X-Original-To: spring@ietfa.amsl.com
Delivered-To: spring@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 1834C120058 for <spring@ietfa.amsl.com>; Wed, 11 Dec 2019 12:32:50 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.999
X-Spam-Level:
X-Spam-Status: No, score=-1.999 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, HTML_MESSAGE=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001] autolearn=unavailable autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=raszuk.net
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 cKGWI3U9S0nV for <spring@ietfa.amsl.com>; Wed, 11 Dec 2019 12:32:48 -0800 (PST)
Received: from mail-qv1-xf31.google.com (mail-qv1-xf31.google.com [IPv6:2607:f8b0:4864:20::f31]) (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 EA603120052 for <spring@ietf.org>; Wed, 11 Dec 2019 12:32:47 -0800 (PST)
Received: by mail-qv1-xf31.google.com with SMTP id c2so6314479qvp.12 for <spring@ietf.org>; Wed, 11 Dec 2019 12:32:47 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=raszuk.net; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=1GnhXXYB/vGevdnmwTfV0YH0E9tQd3zAGqzIkL8H3gQ=; b=LklH9IIpSg/Ex2X9UBL2Hjp2DtQzMlkkaa6wgAmCQWdwShDC9IYOWlHh+F8u9Bka1u UYcxSIfVjxZh8RXcxk/RCWv5ECNP1yQeGxHssidnSod220Rhr+5YjHV+xHoP1hVcH6GO 3/uj7Xwy7MRaIczIbEHPVHZaci+/BQNT/y8BKH5WmXdhSM0m2NvdN8itmvbq8Ujc0b+g qIuVpho2nNvwnOxhg0IxMc5es/+3r3faQ2aM+a8YdZyNVvOxNOy478yrcg7c5ON8By8P CyaScEN6jweSrILojGCqL0rdwLGChLyfHIDh940DPkHR4TRH9IGxcMravs2hGLtQvhiX nawA==
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=1GnhXXYB/vGevdnmwTfV0YH0E9tQd3zAGqzIkL8H3gQ=; b=ciYfBDot8SnC75QMNR+adyY3Sb/sa5P61BVLlQhAvMg3sd7FR8pIETSCwm5OrvQFxU BfTBHE2jyw5XEKLeQX4Ru34bjVW6UFb3iSHqx6KZvWtGuhe/LCPHFismaacwR94Wxdg1 hRTWFKBerjriMtn4FTH9OmfsLfttziZ7ydjL0yvszhVPT5ztbkU4DN8uc2g/YMO3S2XB UqPZhq7fo4dc9hKxdhkxTYpEproDN9ctvJ0IwlScC1fV6vF4MseWnFY1XIWbxC6RHhV1 f7f7z0mWbNqyhY+Yj1+dy88MkBdUAMupEhOnScroU73QbyyLr0TCiZMvvyFpQ6/jBvgM 9koA==
X-Gm-Message-State: APjAAAWH45zJ8wtdwLCN2a3v6grV0X8UXXJGnJ9OsgoR3VSoBecVYYcc pKKESl5KnA4NwVlijSJm9K5+2/D/OOCY7ZguIYC1PQ==
X-Google-Smtp-Source: APXvYqzt47wTI0UmbMSLC6MMIDPwooQF4dn08ZZ2psUksQq+zp34RSBpkRU8m96Y59tH0I61KJcCk6Xb34571cWdvk4=
X-Received: by 2002:a0c:8a31:: with SMTP id 46mr5033800qvt.8.1576096366809; Wed, 11 Dec 2019 12:32:46 -0800 (PST)
MIME-Version: 1.0
References: <f2a0ad13-0eba-6f5a-1d3c-e45e2780f201@si6networks.com> <a2cc5cbd-ac06-e193-307c-3ffe5b21b0b1@si6networks.com> <80A78F48-9802-4DA9-B264-1A8920C1DDF9@kaloom.com> <c727fb5e-015d-90e2-9860-6c48ce021ac4@si6networks.com> <CAOj+MMEyMDHULL7Pr=QmucTJy9b=3ph9TgTZ7koi9BBLkFCJ6g@mail.gmail.com> <bb767aff-8737-a749-2f99-ac350f66def5@si6networks.com> <CAOj+MMEjzxrEbmKbUn11EsTSnVOZC0cKZhAeXapV2vW++g0ZdA@mail.gmail.com> <885c9ad6-ddd2-392a-7e9f-722509753e2d@si6networks.com> <27448_1575983799_5DEF9AB7_27448_30_1_53C29892C857584299CBF5D05346208A48D245CD@OPEXCAUBM43.corporate.adroot.infra.ftgroup> <5b0f37d2-56a3-5f7f-ab29-7d6ebc2367d5@si6networks.com> <CAOj+MMHoAap_7XZs5HSO+a1C18guFzkg1fkov8Wo6ZqHj=xeHQ@mail.gmail.com> <603cbb85-3b68-5c93-e7c5-3768e6310f48@si6networks.com> <CAOj+MMH2rO_YSLrJDEA5G97ad1jMsJHtZDZ-xP+b==smk-J8Dg@mail.gmail.com> <26f2fff6-f6c8-0e9f-29e6-a180896f5a05@si6networks.com> <CAOj+MMHDOgA54mMWq+ko72e9kW7jk=ut8M31c_XNvAx-hXt6qg@mail.gmail.com> <fc55e064-5657-21b6-79e3-6785e0c4c03c@gmail.com>
In-Reply-To: <fc55e064-5657-21b6-79e3-6785e0c4c03c@gmail.com>
From: Robert Raszuk <robert@raszuk.net>
Date: Wed, 11 Dec 2019 21:32:36 +0100
Message-ID: <CAOj+MMGQFZjqoysDaXNK4gk0VEF_W9dbMikRiArzsYZu9652oQ@mail.gmail.com>
To: Brian E Carpenter <brian.e.carpenter@gmail.com>
Cc: Fernando Gont <fgont@si6networks.com>, Bruno Decraene <bruno.decraene@orange.com>, Ron Bonica <rbonica=40juniper.net@dmarc.ietf.org>, SPRING WG <spring@ietf.org>, "int-ads@ietf.org" <int-ads@ietf.org>, Andrew Alston <Andrew.Alston@liquidtelecom.com>, rtg-ads <rtg-ads@ietf.org>, Bob Hinden <bob.hinden@gmail.com>, Ole Troan <otroan@employees.org>, Suresh Krishnan <Suresh@kaloom.com>
Content-Type: multipart/alternative; boundary="000000000000136d96059973887b"
Archived-At: <https://mailarchive.ietf.org/arch/msg/spring/Yn_a-0hpLzjdSqagoXwasDHC3iU>
Subject: Re: [spring] Penultimate Segment Popping and RFC8200 (Was Re: We don't seem to be following our processes (Re: Network Programming - Penultimate Segment Popping))
X-BeenThere: spring@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: "Source Packet Routing in NetworkinG \(SPRING\)" <spring.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/spring>, <mailto:spring-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/spring/>
List-Post: <mailto:spring@ietf.org>
List-Help: <mailto:spring-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/spring>, <mailto:spring-request@ietf.org?subject=subscribe>
X-List-Received-Date: Wed, 11 Dec 2019 20:32:50 -0000

Hi Brian,

I think everyone grasps it. I think the problem is that the SRH proponents
> use the word "insert" a little ambiguously. In IPv6-land, it's been assumed
> to mean "insert an SRH header in the middle of an existing IPv6 packet
> header".
>

Well I got that. In fact I recommend to some friends to rename it in the NP
draft to "impose" or "place" so the text does not raise blood pressure
where it does not to :)

But again as you see from the subject line this discussion is about
deletion not imposition nor insertion. I bet 6man list will be the forum to
discuss Daniel's draft soon.


> I suspect that in SRH-land, and in the IPv6 data plane context, it's mainly
> being used to mean "encapsulate an IPv6 packet in a new IPv6 packet that
> includes
> an SRH header."


I think in the context of SRv6 it was/is used to mean both. Insert SRH with
new header or without one. And the context which exact action is required
is inferred from the situation.

Yes this adds unnecessary confusion and I am sure editors will be happy to
clear this in documents.

Said all this NP draft under this discussion does not have any issue with
any of this.


> And in the MPLS data plane context it means "prepend an additional
> MPLS label."
>

> Right or wrong?
>

Well in MPLS label stack insertion was more called label imposition.

Thx a lot,
R.