IETF Logo Mail Archive

Re: [trill] [rbridge] Query on draft-ietf-trill-esadi-00

Donald Eastlake <d3e3e3@gmail.com> Mon, 01 October 2012 03:49 UTC

Return-Path: <d3e3e3@gmail.com>
X-Original-To: trill@ietfa.amsl.com
Delivered-To: trill@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 75EF121F84C9 for <trill@ietfa.amsl.com>; Sun, 30 Sep 2012 20:49:22 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -103.36
X-Spam-Level:
X-Spam-Status: No, score=-103.36 tagged_above=-999 required=5 tests=[AWL=0.239, BAYES_00=-2.599, RCVD_IN_DNSWL_LOW=-1, USER_IN_WHITELIST=-100]
Received: from mail.ietf.org ([64.170.98.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 2VALvdyhaB-c for <trill@ietfa.amsl.com>; Sun, 30 Sep 2012 20:49:22 -0700 (PDT)
Received: from mail-ie0-f172.google.com (mail-ie0-f172.google.com [209.85.223.172]) by ietfa.amsl.com (Postfix) with ESMTP id CDA9821F84CD for <trill@ietf.org>; Sun, 30 Sep 2012 20:49:21 -0700 (PDT)
Received: by iec9 with SMTP id 9so12880827iec.31 for <trill@ietf.org>; Sun, 30 Sep 2012 20:49:21 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-type; bh=fNLo8/dT8ni0aBHXtYA7TvP7IIbWy5+oSm7z7yN4Lv0=; b=Y1uQ44hBT9pftN8m+efdmp/ALJ6EB/0XK9gl/Qp0NWgRDeAiHDklGkLSnW3i+23WD1 5LwfOJVCB1lkrcVQQbmPqxbcElRCb0TAJVuK4sHJUly4IRyCx0Fd34BI7ktC3ds87GfV wdqTqjNcd3OVij/36RAh3wa2tMqxYaFG1HohFVYEuEE7tFUK1zMKIRVEmX1OFDfOD93U t+76yeF8v5ajwqaEZeW5czr7j7BkkQmoYPwOvpfkWpnLdbdHeSRTonxyDjtVqoRr7e3X b+vcLClhXMRbrLyEY8Rj1f9coiDOvbFj0JxwuH9NS/69gFENmfHTZTxIsi2FR/VDmLno YBnA==
Received: by 10.50.216.167 with SMTP id or7mr4491874igc.73.1349063361353; Sun, 30 Sep 2012 20:49:21 -0700 (PDT)
MIME-Version: 1.0
Received: by 10.64.86.113 with HTTP; Sun, 30 Sep 2012 20:49:01 -0700 (PDT)
In-Reply-To: <CAPFewY0pv8E69czT+qBRh0ViJQjD7s4ZuH2U9OYzJqQUwVc1BA@mail.gmail.com>
References: <CAPFewY0pv8E69czT+qBRh0ViJQjD7s4ZuH2U9OYzJqQUwVc1BA@mail.gmail.com>
From: Donald Eastlake <d3e3e3@gmail.com>
Date: Sun, 30 Sep 2012 23:49:01 -0400
Message-ID: <CAF4+nEH64uuEaTAzeF-sEpSeCzU4=3UjpGXUnwUo4mo9mD06Kg@mail.gmail.com>
To: somnath chatterjee <somnath.chatterjee01@gmail.com>
Content-Type: text/plain; charset="ISO-8859-1"
Cc: trill@ietf.org
Subject: Re: [trill] [rbridge] Query on draft-ietf-trill-esadi-00
X-BeenThere: trill@ietf.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: "Developing a hybrid router/bridge." <trill.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/trill>, <mailto:trill-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/trill>
List-Post: <mailto:trill@ietf.org>
List-Help: <mailto:trill-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/trill>, <mailto:trill-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 01 Oct 2012 03:49:22 -0000

Hi Somnath,

On Thu, Jul 12, 2012 at 8:32 AM, somnath chatterjee
<somnath.chatterjee01@gmail.com> wrote:
> Hi Authors,
>
> I have few comments and a query about  draft-ietf-trill-esadi-00.
>
> 1> Section 4.2 Receipt of ESADI PDUs
>
>    "Because all ESADI instance for VLAN-x are adjacent, when RB1
> receives an ESADI-CSNP from RB2 and detects that it has ESADI-LSPs
> that RB1 is missing, it sets the transmission flag only for its own
> ESADI-LSPs that RB1 is missing. Missing ESADI-LSPs originated by other
> ESADI instances will be detected by those other instances."
>
>    I am not able to understand the quoted sentences.Could you please clarify?

Usually there are only a few RBridges on a link so, if the DRB sends
an IS-IS CSNP that shows it is missing some LSP, other RBridges on the
link will update the DRB by sending the missing LSP -- and that
missing LSP can easily be for some other RBridge that is not on the
link and could not have seen the DRB's CSNP.

But in the ESADI protocol, all the participating RBridges are on the
same physical link so they should all see a CSNP. So there is no
reason for an ESADI RBridge to respond to a CSNP with missing LSPs
that it has that are not its own.

> 2> The figure 2 and 3 in Section 2. ESADI Protocol Overview have the
> Inner MAC DA as "Next Hop Dest. Address"   which should be
> "All-Egress-RBridges" (formerly called "All-ESADI-RBridges")

A new version will be posted soon fixing that.

> 3> In Section 6. ESADI-LSP Contents
>    "ESADI-LSP number zero MUST NOT exceed 1470 minus 24 bytes in
> length (1446 bytes) but if received longer, it is still processed
> normally."
>
>    should be changed to
>
>    "The ESADI payload for ESADI-LSP number zero MUST NOT exceed 1470
> minus 24 bytes in length  (1446 bytes) but if received longer, it is
> still processed normally."

OK.

> Also should it be 1470-24 or Sz-24 ? Sz being the campus wide MTU.

Because, in the current ESADI draft, LSP number zero is used for
sending the priority of RBridges participating in a particular ESADI
instance, it seemed important to but extra careful that LSP number
zero got through. So it should be 1470-24 just like the Hello maximum
is 1470.

Thanks,
Donald
=============================
 Donald E. Eastlake 3rd   +1-508-333-2270 (cell)
 155 Beaver Street, Milford, MA 01757 USA
 d3e3e3@gmail.com

> Thank you,
> Regards,
> Somnath

v2.23.0 | Report a Bug | By Email