Re: [Idr] draft-ietf-idr-bgp-extended-messages-12 WG LC (5/24 to 6/7)

Robert Raszuk <robert@raszuk.net> Thu, 26 May 2016 11:58 UTC

Return-Path: <rraszuk@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 9C85312DE50 for <idr@ietfa.amsl.com>; Thu, 26 May 2016 04:58:39 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.4
X-Spam-Level:
X-Spam-Status: No, score=-2.4 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, FREEMAIL_FORGED_FROMDOMAIN=0.198, FREEMAIL_FROM=0.001, HEADER_FROM_DIFFERENT_DOMAINS=0.001, HTML_MESSAGE=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 h_KWgP05vE5m for <idr@ietfa.amsl.com>; Thu, 26 May 2016 04:58:36 -0700 (PDT)
Received: from mail-lf0-x22a.google.com (mail-lf0-x22a.google.com [IPv6:2a00:1450:4010:c07::22a]) (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 2691012DE45 for <idr@ietf.org>; Thu, 26 May 2016 04:58:36 -0700 (PDT)
Received: by mail-lf0-x22a.google.com with SMTP id b73so9013469lfb.3 for <idr@ietf.org>; Thu, 26 May 2016 04:58:35 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:date:message-id:subject :from:to:cc; bh=8zpe+POdaUuwgoUm4wYjEp5KUXc3mc8ev6gV7KEVzX8=; b=Xi7BpxA385zIZqwRXGyl828j0VvyiCyCWdq4mHSUhUdEU+WY6KdQxn7M+jCvEQpVIj BMQVYco8p0BLSng4NNCbg2XqYW/FrfVusg/RdVaQ7KNWWbGO1tNU/TRnHkcIyEW5QcLw FUfUZHBS4LYpusfBpTvCPfhF+ybV4gLPdT3BdA5dNj8rpjltGJv4Pjby8/hcfvtHU/pE cqcJX0OMzMIUIOlgLo7oRjSBXDmtwNjT8KPnyLllNqOVXxU4Nm0ZeCbE61nXqmPCs8Cz JPbzzmaIWke762GLO122kTxX3kJJMoQFaOGAYbV1cazQ9C9kP3Xv72GHLFvBbgh2XXus XYCQ==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:sender:in-reply-to:references:date :message-id:subject:from:to:cc; bh=8zpe+POdaUuwgoUm4wYjEp5KUXc3mc8ev6gV7KEVzX8=; b=LeKRKZpQsQAZqX+mDS3ZpzhZ5ldn/NBatYGzJy7PkFSLmS/z9Q9BWHCsqDtZEuNgOp oyphUPEEfNP5NDYLOx+jYov5uR30f10eEHa4+9ArozNTjHkatd+0KWdJVcPYp0LKYv8g 4ILrHranARS3qrnrHmEH3r704xr5He/pSO54aH2BftIxCkf9tfCygdzRkYhPaiEH1tmw y71rbLKuSsrMypRxL2nktpzbw8ELaAanrvd0JBiLLATjBstEfbnd5U0cKyf31gj+H2Gq iri7iAikgl9qvFEY21M/MsPc1hKp8pMuy/1QZgjqctcyBeg/boDFMocatAjR8pqo/eGy uzyQ==
X-Gm-Message-State: ALyK8tLHMFw7evXF6azWtoFEiv4pCtDvSdISh+UCX+l9yEHnuxcY+bGQ/P8Yo/Xw2nIXB/RCdM/DHoctuXStEQ==
MIME-Version: 1.0
X-Received: by 10.46.5.82 with SMTP id 79mr77592ljf.64.1464263913849; Thu, 26 May 2016 04:58:33 -0700 (PDT)
Sender: rraszuk@gmail.com
Received: by 10.25.134.196 with HTTP; Thu, 26 May 2016 04:58:33 -0700 (PDT)
In-Reply-To: <m2r3cpnjci.wl%randy@psg.com>
References: <037f01d1b5fc$bfb596f0$3f20c4d0$@ndzh.com> <13146_1464170675_574578B3_13146_4888_1_53C29892C857584299CBF5D05346208A0F8CD227@OPEXCLILM21.corporate.adroot.infra.ftgroup> <CA+b+ERmdpCmCsP-5_NsLH6pbay4zaXMpjGJP2S3z8gfAAXZR8A@mail.gmail.com> <D36B06A7.6257D%acee@cisco.com> <CA+b+ERkioULCYg_HQK9qqN+wjiapTZxK7nHWLGaq_=8wfxajsA@mail.gmail.com> <m2r3cpnjci.wl%randy@psg.com>
Date: Thu, 26 May 2016 13:58:33 +0200
X-Google-Sender-Auth: H4wzPjGl8gMFdoP-LsWg8BHKlNs
Message-ID: <CA+b+ER=pp56jG_CFN7TGfwgM-ccFpn8B_Ptsfe5RG6q-aSPWzg@mail.gmail.com>
From: Robert Raszuk <robert@raszuk.net>
To: Randy Bush <randy@psg.com>
Content-Type: multipart/alternative; boundary="001a1148e6f0714e120533bd8227"
Archived-At: <http://mailarchive.ietf.org/arch/msg/idr/JurZ7hG2G_osF6zGqz9YEEyoxCE>
Cc: idr wg list <idr@ietf.org>
Subject: Re: [Idr] draft-ietf-idr-bgp-extended-messages-12 WG LC (5/24 to 6/7)
X-BeenThere: idr@ietf.org
X-Mailman-Version: 2.1.17
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: Thu, 26 May 2016 11:58:39 -0000

>  if there is prepend insanity, that would die today.

The difference is that today it will immediately die at yr peer and it is
very easy to detect. Same for other attributes which can take tons of stuff
loaded on them today.

With extended message it will die few hops away likely in different AS and
to detect it will be quite hard without proper tool.

Thx,
R.





On Thu, May 26, 2016 at 1:34 PM, Randy Bush <randy@psg.com> wrote:

> packing is not relevant.  receiver unpacks if nlri are packed, and as a
> sender decides whether and how densly to pack or not.  if the outbound
> link is smaller than the inbound, pack in less nlri.  if it is the
> attributes that over-flow, then you have a more general problem.
>
> if we are in the bgpsec space,
>
>   o will a single nlri with a signed path fit in the extended message?
>     yes.  even degenerate prepends don't hurt because of the pCount
>     hack.
>
>   o if there is an outbound that is not a bgpsec speaker, they will be
>     sent a classic as4_path which darn well should fit in the classic
>     message size.  if there is prepend insanity, that would die today.
>
>   o if the outbound is a bgpsec speaker yet will not use an extended
>     message size, there is one interesting case, the singleton stub.
>     a non-transit router can sign toward its upstream(s) and not care
>     about receiving bgsec as it has no other choice of where to send
>     packets.
>
> randy
>