Re: [CCAMP] Network Assigned Upstream Label - Draft Update

Vishnu Pavan Beeram <vishnupavan@gmail.com> Fri, 28 February 2014 12:26 UTC

Return-Path: <vishnupavan@gmail.com>
X-Original-To: ccamp@ietfa.amsl.com
Delivered-To: ccamp@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id E08BA1A025F for <ccamp@ietfa.amsl.com>; Fri, 28 Feb 2014 04:26:54 -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, FREEMAIL_FROM=0.001, HTML_MESSAGE=0.001, SPF_PASS=-0.001] autolearn=ham
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 249lEz4LOCSR for <ccamp@ietfa.amsl.com>; Fri, 28 Feb 2014 04:26:51 -0800 (PST)
Received: from mail-ee0-x22c.google.com (mail-ee0-x22c.google.com [IPv6:2a00:1450:4013:c00::22c]) by ietfa.amsl.com (Postfix) with ESMTP id 6642E1A025E for <ccamp@ietf.org>; Fri, 28 Feb 2014 04:26:51 -0800 (PST)
Received: by mail-ee0-f44.google.com with SMTP id d49so2233030eek.3 for <ccamp@ietf.org>; Fri, 28 Feb 2014 04:26:49 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=roO7TQ0HYl5caeiwxR7FftO8bNcFkJxfy125uZzuYHc=; b=lBL5MGVyh7zKZir9d2c+oTMj/gAaU9/0tiottJ3frhhXWFPLuS90AeT6AxO0PwPjaD he8FS5fubZvmr0lrhWxck18MZyhrlZ6JT0PW3X8Ius3h0SpHt0GbaeeAlEy4VuF+0qvs ts04XGjFUYCNwUdC91dfqXfwZiZm4vJmgd4dFzfQb89HYBIBSIt3j+F2TQKmAiNct8bn 9WUpYlzZV5LyvJSsZPTnu+JGioZ28qAnIyoMDwQ/Ft//h02l2TLti2S3XQ+CPM+xBbVs uppLVgLYJfUvXOKkNY+mxReHcHru9BcZIIqKEYBKYIpseQoIvxHsZ+aKdag/vHzd4KPu 4AQg==
MIME-Version: 1.0
X-Received: by 10.204.72.9 with SMTP id k9mr4403192bkj.1.1393590409046; Fri, 28 Feb 2014 04:26:49 -0800 (PST)
Received: by 10.204.64.68 with HTTP; Fri, 28 Feb 2014 04:26:48 -0800 (PST)
In-Reply-To: <CF323F23.9C8CD%zali@cisco.com>
References: <CA+YzgTuUQzfjnjTWdya7xgpytB+nBvY_d-Sx4faqUJY3Md9h5Q@mail.gmail.com> <CF323F23.9C8CD%zali@cisco.com>
Date: Fri, 28 Feb 2014 07:26:48 -0500
Message-ID: <CA+YzgTtxz-aQXx8d5EV0kP05DV9NCAdUdbAmV0pK7nECo+KvFw@mail.gmail.com>
From: Vishnu Pavan Beeram <vishnupavan@gmail.com>
To: "Zafar Ali (zali)" <zali@cisco.com>
Content-Type: multipart/alternative; boundary="001a1132f3264b5d8e04f3768d30"
Archived-At: http://mailarchive.ietf.org/arch/msg/ccamp/DNK1tQ37-OcKiqc3wBh8GQ0TQEQ
Cc: "ccamp@ietf.org" <ccamp@ietf.org>
Subject: Re: [CCAMP] Network Assigned Upstream Label - Draft Update
X-BeenThere: ccamp@ietf.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: Discussion list for the CCAMP working group <ccamp.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/ccamp>, <mailto:ccamp-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/ccamp/>
List-Post: <mailto:ccamp@ietf.org>
List-Help: <mailto:ccamp-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ccamp>, <mailto:ccamp-request@ietf.org?subject=subscribe>
X-List-Received-Date: Fri, 28 Feb 2014 12:26:55 -0000

Zafar, Hi!

We have been through this before (you'll find this point well debated in
the thread archives - thread-pointer:
http://www.ietf.org/mail-archive/web/ccamp/current/msg15444.html) and I
thought you agreed to the need for an Unassigned Upstream Label. Anyway,
let me try this again -

Here are a couple of points that have been made earlier:
(1) As per the existing procedures for UPSTREAM_LABEL (RFC 3473), the
presence of an assigned label in the object indicates that the
upstream-node has already installed/programmed this label on its outgoing
interface. That isn't the case in your proposal.
(2) The use of Label-Set/Acceptable Label-Set was meant to be used for
exceptions. Using it always for every setup request is a compromised
solution.

Regards,
-Pavan




On Thu, Feb 27, 2014 at 11:41 PM, Zafar Ali (zali) <zali@cisco.com> wrote:

>
>
>   From: Vishnu Pavan Beeram <vishnupavan@gmail.com>
> Date: Tuesday, February 25, 2014 7:54 AM
> To: "Zhangxian (Xian)" <zhang.xian@huawei.com>
> Cc: "ccamp@ietf.org" <ccamp@ietf.org>
> Subject: Re: [CCAMP] Network Assigned Upstream Label - Draft Update
>
>    2)      In this draft, it is assumed that the label assigned will
>> always be symmetric (i.e., upstream and downstream label is equal). Thus,
>> IMHO, using the mechanism specified by RFC3473 for unidirectional LSP setup
>> (i.e., downstream label assigned by the destination node will also enable
>> upstream label selected) can solve the problem. It does not require
>> protocol extensions, although probably some operational policy should be in
>> force to ask the nodes in the data plane to configure the resource in both
>> directions. How do you see your solution better/different than this one?
>>
>  [VPB] If I understood what you are saying - your suggestion is to signal
> the Lambda LSP as a uni-directional LSP (no UPSTREAM-LABEL) and have some
> policy at each hop requesting the implementation to ignore the signaled
> "uni-directionality" and assign the labels in both directions for the LSP.
> (Did I understand that right?)
>  Yes, you could do that. And you could also use this policy based approach
> (overriding signaled objects) for a number of other signaled attributes of
> an LSP. The obvious advantage of having a signaling based solution is that
> you wouldn't need explicit policy to be configured/implemented at each hop
> along the path of the LSP.
>
>
>  Pavan:
>
>  When (alien) wavelength is same in forward and reverse direction, we can
> use label set along with acceptable label set - as defined in RFC3473.
>
>  Thanks
>
>  Regards ... Zafar
>