RE: [mpls] draft-ietf-mpls-p2mp-sig-requirement-00.txt
neil.2.harrison@bt.com Wed, 22 December 2004 04:46 UTC
Received: from ietf-mx.ietf.org (ietf-mx.ietf.org [132.151.6.1]) by ietf.org (8.9.1a/8.9.1a) with ESMTP id XAA17873; Tue, 21 Dec 2004 23:46:21 -0500 (EST)
Received: from megatron.ietf.org ([132.151.6.71]) by ietf-mx.ietf.org with esmtp (Exim 4.33) id 1CgyXs-0000JS-34; Tue, 21 Dec 2004 23:56:20 -0500
Received: from localhost.localdomain ([127.0.0.1] helo=megatron.ietf.org) by megatron.ietf.org with esmtp (Exim 4.32) id 1CgyK5-00067S-1F; Tue, 21 Dec 2004 23:42:05 -0500
Received: from odin.ietf.org ([132.151.1.176] helo=ietf.org) by megatron.ietf.org with esmtp (Exim 4.32) id 1CgyEl-0003Ds-M7 for mpls@megatron.ietf.org; Tue, 21 Dec 2004 23:36:35 -0500
Received: from ietf-mx.ietf.org (ietf-mx.ietf.org [132.151.6.1]) by ietf.org (8.9.1a/8.9.1a) with ESMTP id XAA17080 for <mpls@ietf.org>; Tue, 21 Dec 2004 23:36:32 -0500 (EST)
From: neil.2.harrison@bt.com
Received: from smtp3.smtp.bt.com ([217.32.164.138]) by ietf-mx.ietf.org with esmtp (Exim 4.33) id 1CgyOM-0008Ru-Qa for mpls@ietf.org; Tue, 21 Dec 2004 23:46:31 -0500
Received: from i2km97-ukbr.domain1.systemhost.net ([193.113.197.30]) by smtp3.smtp.bt.com with Microsoft SMTPSVC(6.0.3790.80); Wed, 22 Dec 2004 04:37:24 +0000
Received: from i2km07-ukbr.domain1.systemhost.net ([193.113.197.26]) by i2km97-ukbr.domain1.systemhost.net with Microsoft SMTPSVC(5.0.2195.6713); Wed, 22 Dec 2004 04:37:23 +0000
X-MimeOLE: Produced By Microsoft Exchange V6.0.6556.0
content-class: urn:content-classes:message
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
Subject: RE: [mpls] draft-ietf-mpls-p2mp-sig-requirement-00.txt
Date: Wed, 22 Dec 2004 04:37:23 -0000
Message-ID: <0536FC9B908BEC4597EE721BE6A353890A9F16B7@i2km07-ukbr.domain1.systemhost.net>
Thread-Topic: [mpls] draft-ietf-mpls-p2mp-sig-requirement-00.txt
Thread-Index: AcTnqLlFjr28D8XqSDy9mSF53obLngAL/jxw
To: tnadeau@cisco.com, adrian@olddog.co.uk
X-OriginalArrivalTime: 22 Dec 2004 04:37:23.0543 (UTC) FILETIME=[EE541E70:01C4E7DF]
X-Spam-Score: 0.3 (/)
X-Scan-Signature: d8ae4fd88fcaf47c1a71c804d04f413d
Content-Transfer-Encoding: quoted-printable
Cc: mpls@ietf.org
X-BeenThere: mpls@lists.ietf.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Multi-Protocol Label Switching WG <mpls.lists.ietf.org>
List-Unsubscribe: <https://www1.ietf.org/mailman/listinfo/mpls>, <mailto:mpls-request@lists.ietf.org?subject=unsubscribe>
List-Archive: <http://www1.ietf.org/pipermail/mpls>
List-Post: <mailto:mpls@lists.ietf.org>
List-Help: <mailto:mpls-request@lists.ietf.org?subject=help>
List-Subscribe: <https://www1.ietf.org/mailman/listinfo/mpls>, <mailto:mpls-request@lists.ietf.org?subject=subscribe>
Sender: mpls-bounces@ietf.org
Errors-To: mpls-bounces@ietf.org
X-Spam-Score: 0.3 (/)
X-Scan-Signature: bdc523f9a54890b8a30dd6fd53d5d024
Content-Transfer-Encoding: quoted-printable
Tom, <snipped> Tom N said 21 December 2004 21:25 > > 4.18 P2MP MPLS OAM > > > > Management of P2MP LSPs is as important as the management of P2P > > LSPs. > > > > The MPLS and GMPLS MIB modules MUST be enhanced to > provide P2MP TE > > LSP management. > > > > In order to facilitate correct management, P2MP TE LSPs MUST have > > unique identifiers. > > I don't see why the second or third sentences need to > be a MUST, especially since they have no corresponding justification. NH=> One of the things that has concerned me for a long time is that we do not have a consistent way of addressing the access points of MPLS LSPs......their addressing is currently a function of the signalling used. This is wrong. The access point addresses of the traffic data-plane trails should have nothing to do with the control-plane, and they should be the SAME no matter how the trail is instantiated, ie by signalling protocol X, Y or Z or by management provisioning. Why? Because a CV OAM function is a common theme to all network modes. This 'comes for free' in the cl-ps mode as each pkt constains a SA, but we have to consciously add this CV function to the co modes. Using the SA is an obvious and natural way to provide this CV function. Thus, if 2 trails interfere with each other (eg swaps or misbranch/mismerge) one wants a consistent and simple method of defect detection across the whole trail population no matter how the trail was instantiated. Now I am not sure what whoever wrote the above had in mind, but in my view the above point is relevant and provides a strong justification. In the case of a p2mp construction one is obviously sending the SAME SA in a CV function to all the sinks....which is indeed the correct behaviour. Providing we have the SAME CV mechanism on both p2p and p2mp constructions AND it is unidirectional (for the reasons I gave in my previous mail) then we can clearly handle defects BETWEEN p2p and p2mp constructions in a similar manner. Surely that has to be a good/simplifying property. > > > OAM facilities will have special demands in P2MP environments > > especially within the context of tracing the paths and > connectivity > > of P2MP TE LSPs. The precise requirements and mechanisms > for OAM are > > out of the scope of this document. It is expected that a separate > > document will cover these requirements. > > This sentence seems to indicate that precise OAM > requirements are out of the scope of this document -- so why > then do the preceding two sentences provide requirements for > OAM for p2mp TE LSPs?! Based on this, the preceding two > sentences should be removed from this document and put into a > place where there are in the scope of the document (i.e.: > MPLS OAM Requirements). :P NH=> Fair point PROVIDING the requirements clearly address the right behaviour. I think we have to differentiate the 2 cases of OAM: - simple 'always-on' defect detection/handling stuff.....the base requirement being the CV and FDI (higher layer alarm suppression) functions; - the more complex 'on-demand' diagnostic and PM functions....and whilst the former defect detection/handling OAM can (and should) be harmonised across both p2p and p2mp cases for the reasons I gave above, I can imagine that diagnostics and PM OAM requirements are going to be somewhat different (generally more complex for the p2mp case). regards, Neil _______________________________________________ mpls mailing list mpls@lists.ietf.org https://www1.ietf.org/mailman/listinfo/mpls
- RE: [mpls] draft-ietf-mpls-p2mp-sig-requirement-0… neil.2.harrison
- Re: [mpls] draft-ietf-mpls-p2mp-sig-requirement-0… Monique Morrow
- RE: [mpls] draft-ietf-mpls-p2mp-sig-requirement-0… neil.2.harrison