Re: [rrg] procedural aggregation

William Herrin <bill@herrin.us> Wed, 12 March 2014 02:59 UTC

Return-Path: <wherrin@gmail.com>
X-Original-To: rrg@ietfa.amsl.com
Delivered-To: rrg@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 389631A08D6 for <rrg@ietfa.amsl.com>; Tue, 11 Mar 2014 19:59:52 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: 0.621
X-Spam-Level:
X-Spam-Status: No, score=0.621 tagged_above=-999 required=5 tests=[BAYES_40=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, FM_FORGED_GMAIL=0.622, FREEMAIL_FROM=0.001, SPF_PASS=-0.001] autolearn=no
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 SIcN7mrVb215 for <rrg@ietfa.amsl.com>; Tue, 11 Mar 2014 19:59:50 -0700 (PDT)
Received: from mail-ve0-x230.google.com (mail-ve0-x230.google.com [IPv6:2607:f8b0:400c:c01::230]) by ietfa.amsl.com (Postfix) with ESMTP id B08151A08D3 for <rrg@irtf.org>; Tue, 11 Mar 2014 19:59:50 -0700 (PDT)
Received: by mail-ve0-f176.google.com with SMTP id cz12so9355414veb.21 for <rrg@irtf.org>; Tue, 11 Mar 2014 19:59:44 -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:from:date:message-id :subject:to:content-type; bh=eAKq4RHqvDCkYe+Ma4h7yJAvu2LtADwhZ5RbkFFmvdo=; b=uLxeaWOaxZmsgxFVAw36K6FyQHQT5vumzn4EDLSHNrDaYKl6/lY1eLc8Cy4hg55/r8 vVkbUP7DSDr7cVbX173Kl98abQaZ2lLKaFeoGKY+viVjQTkRC3oFOuCHDdG8peFLVmqH pud3OiPSq1BIAekdu8ipsb1sAwYO1deBrGIiygeNimRquvFtpXVK/GMsRrptrUsSzTjP wLVvyQY5VQR5EfjjA8LesiMAeEFPDPki6Y3zrTFA7ZSzfD6rea+Vvag8QvBYGQXsYF37 5tBe1maY+hQyUa7RUnFHkVS5IkaT9vWK0575VhXU3CI/a3Qatu6nAmFyuS2zvq3nR1z1 oAuQ==
X-Received: by 10.220.250.203 with SMTP id mp11mr29920075vcb.2.1394593184579; Tue, 11 Mar 2014 19:59:44 -0700 (PDT)
MIME-Version: 1.0
Sender: wherrin@gmail.com
Received: by 10.52.38.234 with HTTP; Tue, 11 Mar 2014 19:59:24 -0700 (PDT)
In-Reply-To: <CAP-guGUerSYu+Xy4FJ+3EUTn-j45CAF0hSU=cpR61XeKZW9gvg@mail.gmail.com>
References: <CAP-guGXyxehmCiskATSLOouE0Cx1i9KFroK60r=xWe-Lu7peSA@mail.gmail.com> <8D106691E2F8808-2798-932B@webmail-d162.sysops.aol.com> <CAP-guGU4QCHSOnr99hhvksNa8=zm_OZ9bR34HhHv7WCK55sVvw@mail.gmail.com> <5317511D.20506@joelhalpern.com> <CAP-guGVEXDe=YBgGd4Y_kSTsoRH+osfNvqmd+9KwB5pY3C6x-g@mail.gmail.com> <53176AF6.1040308@joelhalpern.com> <CAP-guGUerSYu+Xy4FJ+3EUTn-j45CAF0hSU=cpR61XeKZW9gvg@mail.gmail.com>
From: William Herrin <bill@herrin.us>
Date: Tue, 11 Mar 2014 22:59:24 -0400
X-Google-Sender-Auth: bX00kyXIclMwzhC4ZRg64p0-NM4
Message-ID: <CAP-guGWzWC7wuL+HVF5bBitYLFoGBtf0EWoKoDdsMV-2fYRdJA@mail.gmail.com>
To: RRG <rrg@irtf.org>
Content-Type: text/plain; charset="ISO-8859-1"
Archived-At: http://mailarchive.ietf.org/arch/msg/rrg/9NhuJfwejr9owrXiDGmx7sZk7WU
Subject: Re: [rrg] procedural aggregation
X-BeenThere: rrg@irtf.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: IRTF Routing Research Group <rrg.irtf.org>
List-Unsubscribe: <http://www.irtf.org/mailman/options/rrg>, <mailto:rrg-request@irtf.org?subject=unsubscribe>
List-Archive: <http://www.irtf.org/mail-archive/web/rrg/>
List-Post: <mailto:rrg@irtf.org>
List-Help: <mailto:rrg-request@irtf.org?subject=help>
List-Subscribe: <http://www.irtf.org/mailman/listinfo/rrg>, <mailto:rrg-request@irtf.org?subject=subscribe>
X-List-Received-Date: Wed, 12 Mar 2014 02:59:52 -0000

Hi Folks,

Here's another circumstance worth mentioning. This particular one is
an undesirable case that exists in BGP today. It would be better if it
didn't work. When I get to procedural aggregation, it'll be important
to consider whether my notions make this scenario worse.

You have three networks: A, B and C. A peers with B, B peers with C.

A-B-C

You have a customer, W. W buys transit service from A (gige) and B (T1).

A-B-C
| /
W

W announces 10.1.2.0/23 to B and announces 10.1.2.0/24 plus 10.1.3.0/24 to A.

Because W is a customer, B announces 10.1.2.0/23 to C but as soon as
the packet arrives at B from C, B sends it to A because of the more
specific route it heard from A.

This allows W to draw a gige of traffic through B even though he's
only paying for a T1.

Regards,
Bill Herrin


-- 
William D. Herrin ................ herrin@dirtside.com  bill@herrin.us
3005 Crane Dr. ...................... Web: <http://bill.herrin.us/>
Falls Church, VA 22042-3004