Re: [Idr] Vendor Defaults (was Re: Review of draft-ietf-large-community-06.txt)

Robert Raszuk <robert@raszuk.net> Sun, 06 November 2016 23:30 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 AE0C0129A4D for <idr@ietfa.amsl.com>; Sun, 6 Nov 2016 15:30:54 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.399
X-Spam-Level:
X-Spam-Status: No, score=-2.399 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, FREEMAIL_FORGED_FROMDOMAIN=0.199, 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 npn31qQSi-Zz for <idr@ietfa.amsl.com>; Sun, 6 Nov 2016 15:30:52 -0800 (PST)
Received: from mail-wm0-x235.google.com (mail-wm0-x235.google.com [IPv6:2a00:1450:400c:c09::235]) (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 68195129A4E for <idr@ietf.org>; Sun, 6 Nov 2016 15:30:52 -0800 (PST)
Received: by mail-wm0-x235.google.com with SMTP id a197so151130678wmd.0 for <idr@ietf.org>; Sun, 06 Nov 2016 15:30:52 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:from:date:message-id :subject:to:cc; bh=P+Y4K2C8KaW2ig+OAG3MzkBJcvERhkglw05q5wam5mE=; b=y1uqUIv0xKSC/wrymfBpk0VLLtiGuANmY+B97HNwBCs46DMjRQPPLJ9eQF42n4bYdb SM+O3Ue38ysY4S1aHqz05k+gGN4TZXd0OjIL/putexfm6ihgfvkBZvR0/5OkeStnm3x2 mpRIi4t6/7wISNzCghsvaKMN1VHmQtbZe51Tpy8ijxYDkhH/jGGAOKMV7wI1u2W5OaAR TJIRr0l7A9HgblOzsgZbBItHNxd3g6YWcO1gv+w7NkiSTfFLRKOA9gJO1ynS/bPIJnlu ZVcm1iwUri7oOgKjg/ahTPbd/1q5/Lu5fCqq+LwTpb0+uG9KAJoPxXsEXS3QVAcRyYfW VzkQ==
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:from :date:message-id:subject:to:cc; bh=P+Y4K2C8KaW2ig+OAG3MzkBJcvERhkglw05q5wam5mE=; b=deRuZT6c97nhAd5xD9XqkDutwjXP7Ub7kaBZqjheAgMkXaAz7hbceiPkbddLrOQW83 H8aeGgfWQMfNOI64F4XaZF6y8KZ9+PYUhsqXs4ka0hErTa00U54PumMaJp/68nBJwwj2 6yJRzyk3wmKXImwM2eNKQLt/oZ4uAlsKetQdGpkYdxFcXk7RcIQ7WZMj/zXy+zoxfC95 haty3TAI8lQyvQvGjL2/yvaGmG0Me1voXiXmtX0wVpSiRQkLNTf4WGowvpOcjSm8d41C fZp40/U2iOIgwXX4NOCzr5krv/+xGCJ/LA/y97tWTdWmFTJq5RW1dlwyb0cmwr3a2x7e wdwA==
X-Gm-Message-State: ABUngvdA0Y/Mlrb3Y6V9LG/Jnal8RV7vHjMorlruPNz3ilV4xRjf45P9Bi5NGZflSP755LiUCMOyaVvZ44UUSw==
X-Received: by 10.28.17.134 with SMTP id 128mr4503373wmr.17.1478475050813; Sun, 06 Nov 2016 15:30:50 -0800 (PST)
MIME-Version: 1.0
Sender: rraszuk@gmail.com
Received: by 10.80.137.69 with HTTP; Sun, 6 Nov 2016 15:30:49 -0800 (PST)
In-Reply-To: <6CAFC026-6102-42BF-97FA-779457D84ECE@cisco.com>
References: <CAH1iCiq6jNtnkta0Bt952EQ9zOKSGt=_cCySsT5XuOKuHYO2nQ@mail.gmail.com> <86860386-9C2B-4BD5-B457-2A6DA5446CF3@cisco.com> <17E646EF-4633-423B-9AC4-B53D49C90632@gmail.com> <6CAFC026-6102-42BF-97FA-779457D84ECE@cisco.com>
From: Robert Raszuk <robert@raszuk.net>
Date: Mon, 7 Nov 2016 00:30:49 +0100
X-Google-Sender-Auth: mvwWoQXsdecBi4BcTGDlbl8RlVg
Message-ID: <CA+b+ERm5VVz520OhgXYTFOt9_M6_=MHLE9M-=1T+wnfw7RY83Q@mail.gmail.com>
To: "Jakob Heitz (jheitz)" <jheitz@cisco.com>
Content-Type: multipart/alternative; boundary=001a114706703690580540aa4cfd
Archived-At: <https://mailarchive.ietf.org/arch/msg/idr/PLTnvWO13qx91xmv0jR6ub9asgQ>
Cc: "idr@ietf.org" <idr@ietf.org>
Subject: Re: [Idr] Vendor Defaults (was Re: Review of draft-ietf-large-community-06.txt)
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: Sun, 06 Nov 2016 23:30:54 -0000

Hi Jakob,

Very fair and good summary !

One question: What is "unintended routing" ? Are you alluding to "churn" If
so pls see my reply to previous post.

Just to reiterate ... I do recommend that whatever option gets more support
it should be spelled out in the Large Community RFC such that all
implementations can be consistent.

Best,
Robert


On Mon, Nov 7, 2016 at 12:25 AM, Jakob Heitz (jheitz) <jheitz@cisco.com>
wrote:

> The question:
> Should Large Communities be transmitted across EBGP by default?
>
> Note: there is a knob to change the default, so the discussion is how to
> act with the knob unconfigured.
>
> Arguments to block:
> 1. Principle of least surprise: Do same as 1997.
> 2. Accidental leakage of internally used communities will cause unintended
> routing.
>
> Arguments to pass:
> 1. Legacy code will pass it, because the attribute is transitive. Upgrade
> to LC aware code should do the same by default.
> 2. It is convenient to pass a community through your first level transit
> to fix a problem further upstream. A default block frustrates this effort.
>
> The problem of accidental leakage is greater with 1997 communities,
> because many ISPs use private ASNs. This is as problem if a community
> intended for a distant ISP is interpreted by a near ISP when they use the
> same private ASN. This problem SHOULD disappear with Large Communities,
> because the need to use private ASNs no longer exists.
>
> I would like to hear other arguments and gauge support for each case.
>
> Thanks,
> Jakob.
>
> _______________________________________________
> Idr mailing list
> Idr@ietf.org
> https://www.ietf.org/mailman/listinfo/idr
>