IETF Logo Mail Archive

Re: [mpls-tp] [PWE3] Proposal of using GAL for PW

"BUSI, ITALO (ITALO)" <italo.busi@alcatel-lucent.com> Mon, 05 July 2010 12:29 UTC

Return-Path: <italo.busi@alcatel-lucent.com>
X-Original-To: mpls-tp@core3.amsl.com
Delivered-To: mpls-tp@core3.amsl.com
Received: from localhost (localhost [127.0.0.1]) by core3.amsl.com (Postfix) with ESMTP id 01DBC3A68BC; Mon, 5 Jul 2010 05:29:57 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -5.248
X-Spam-Level:
X-Spam-Status: No, score=-5.248 tagged_above=-999 required=5 tests=[AWL=1.000, BAYES_00=-2.599, HELO_EQ_FR=0.35, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_MED=-4]
Received: from mail.ietf.org ([64.170.98.32]) by localhost (core3.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 1n5zzj4tChQb; Mon, 5 Jul 2010 05:29:56 -0700 (PDT)
Received: from smail3.alcatel.fr (smail3.alcatel.fr [64.208.49.56]) by core3.amsl.com (Postfix) with ESMTP id A9CDA3A68A5; Mon, 5 Jul 2010 05:29:55 -0700 (PDT)
Received: from FRMRSSXCHHUB03.dc-m.alcatel-lucent.com (FRMRSSXCHHUB03.dc-m.alcatel-lucent.com [135.120.45.63]) by smail3.alcatel.fr (8.14.3/8.14.3/ICT) with ESMTP id o65CRQP3016856 (version=TLSv1/SSLv3 cipher=RC4-MD5 bits=128 verify=NOT); Mon, 5 Jul 2010 14:29:27 +0200
Received: from FRMRSSXCHMBSB1.dc-m.alcatel-lucent.com ([135.120.45.40]) by FRMRSSXCHHUB03.dc-m.alcatel-lucent.com ([135.120.45.63]) with mapi; Mon, 5 Jul 2010 14:28:48 +0200
From: "BUSI, ITALO (ITALO)" <italo.busi@alcatel-lucent.com>
To: Alexander Vainshtein <Alexander.Vainshtein@ecitele.com>, "stbryant@cisco.com" <stbryant@cisco.com>, Shahram Davari <davari@broadcom.com>
Date: Mon, 5 Jul 2010 14:28:47 +0200
Thread-Topic: [PWE3] [mpls-tp] Proposal of using GAL for PW
Thread-Index: AcsZyGN0IxBPyQW3RsiJBXvOYSLH1gCUsC9QAABmbbAAASc48A==
Message-ID: <15740615FC9674499FBCE797B011623F0B730196@FRMRSSXCHMBSB1.dc-m.alcatel-lucent.com>
References: <2C2F1EBA8050E74EA81502D5740B4BD6940E809263@SJEXCHCCR02.corp.ad.broadcom.com> <C8529DB4.4489A%giles.heron@gmail.com> <2C2F1EBA8050E74EA81502D5740B4BD6940E80926C@SJEXCHCCR02.corp.ad.broadcom.com> <4C2DB03F.7000709@cisco.com> <15740615FC9674499FBCE797B011623F0B730021@FRMRSSXCHMBSB1.dc-m.alcatel-lucent.com> <A3C5DF08D38B6049839A6F553B331C76D37F569A3D@ILPTMAIL02.ecitele.com>
In-Reply-To: <A3C5DF08D38B6049839A6F553B331C76D37F569A3D@ILPTMAIL02.ecitele.com>
Accept-Language: en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
acceptlanguage: en-US
Content-Type: multipart/alternative; boundary="_000_15740615FC9674499FBCE797B011623F0B730196FRMRSSXCHMBSB1d_"
MIME-Version: 1.0
X-Scanned-By: MIMEDefang 2.64 on 155.132.188.83
Cc: "lihan@chinamobile.com" <lihan@chinamobile.com>, "pwe3@ietf.org" <pwe3@ietf.org>, "mpls-tp@ietf.org" <mpls-tp@ietf.org>
Subject: Re: [mpls-tp] [PWE3] Proposal of using GAL for PW
X-BeenThere: mpls-tp@ietf.org
X-Mailman-Version: 2.1.9
Precedence: list
List-Id: MPLS-TP Mailing list <mpls-tp.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/listinfo/mpls-tp>, <mailto:mpls-tp-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/mpls-tp>
List-Post: <mailto:mpls-tp@ietf.org>
List-Help: <mailto:mpls-tp-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/mpls-tp>, <mailto:mpls-tp-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 05 Jul 2010 12:29:57 -0000

Sasha,

what you say is correct but it is applicable to any environment where you use OAM together with ECMP. I do not see anything specific with GAL and PW.

Italo

________________________________
From: Alexander Vainshtein [mailto:Alexander.Vainshtein@ecitele.com]
Sent: lunedì 5 luglio 2010 10.39
To: BUSI, ITALO (ITALO); stbryant@cisco.com; Shahram Davari
Cc: lihan@chinamobile.com; pwe3@ietf.org; mpls-tp@ietf.org
Subject: RE: [PWE3] [mpls-tp] Proposal of using GAL for PW

Hi all,
IMHO and FWIW, while RFC 5586  (5886 looks like a typo to me) does not place any restrictions on using GAL in non-TP environments, its usefulness in these environments (where various forms of multipath, including usage of entropy labels,  cannot be precluded) for OAM purposes is somewhat problematic:
Adding GAL to the label stack changes this for the multipath mechanisms based on stack hashing, and fate-sharing of OAM and user traffic packets is not guaranteed any more.

My 2c,
     Sasha

From: pwe3-bounces@ietf.org [mailto:pwe3-bounces@ietf.org] On Behalf Of BUSI, ITALO (ITALO)
Sent: Monday, July 05, 2010 11:17 AM
To: stbryant@cisco.com; Shahram Davari
Cc: lihan@chinamobile.com; pwe3@ietf.org; mpls-tp@ietf.org
Subject: Re: [PWE3] [mpls-tp] Proposal of using GAL for PW

I agree with Stewart.

The GAL MUST be at the BoS in MPLS-TP where ECMP is not applicable and entroy labels MUST NOT be used.

In other MPLS environments (e.g., where entropy labels are used), RFC 5886 does not place any restriction on the position of the GAL within the label stack.

Italo

________________________________
From: mpls-tp-bounces@ietf.org [mailto:mpls-tp-bounces@ietf.org] On Behalf Of Stewart Bryant
Sent: venerdì 2 luglio 2010 11.24
To: Shahram Davari
Cc: Andy Malis; mpls-tp@ietf.org; lihan@chinamobile.com; pwe3@ietf.org; HUANG, Feng F (Feng)
Subject: Re: [mpls-tp] [PWE3] Proposal of using GAL for PW
On 01/07/2010 19:35, Shahram Davari wrote:
!mmm so if one used entropy then they can't have OAM?
-SD

Not so. The GAL goes above the entropy label (S=0), so gets parsed first. This works for both PHP and not PHP, and both LSP and PW.

- Stewart

v2.8.7 | Report a Bug | By Email