From: firstname.lastname@example.org [mailto:email@example.com]On Behalf Of zafar ali
Sent: Monday, October 20, 2003 9:48 AM
Cc: 'zafar ali'; firstname.lastname@example.org; Dimitri.Papadimitriou@alcatel.be; 'Adrian Farrel'; 'Kireeti Kompella'
Subject: Component Link Recording for TE Link Bundles (draft-zamfir-explicit-resource-control-bundle-01.txt has been updated)Dear Ccamp'ers:
This is a follow-up on our AI from last ccamp WG meeting on the above-mentioned ID. We don’t think the crux of this ID came across right, during the presentation and the follow-up questions and answers. As Zafar mentioned during the ccamp wg meeting discussions, this ID mainly addresses problem that exists in the RRO. Specifically, when TE links are bundled, identification of label resource in RRO is not enough for the administrative purpose. Network service providers would like to know the component link that is being used by a given the LSP. In other words, when link bundling is used, resource recording requires mechanisms to specify the component link identifier, along the TE link identifier and Label.
In current specification, we cannot record component link selected by an intermediate node in the RRO, which posses an administrative deficiency. The ID mainly addresses this shortage by defining the extensions to RSVP-TE to specify component link identifiers for resource recording in a network containing TE link (a.k.a. link bundles).
This is true that the ID also defines the ERO counter-part. It seems from our last meeting discussions that one shall try to maintain as symmetry between the ERO and RRO definitions as much as possible. Nonetheless, the ERO definition also addresses a current deficiency in the standard definition. Specifically, explicit resource control for bi-directional LSP when forward and reverse legs of the LSP are to follow different component links within a TE bundle is not possible using current specification. But for the time being, this is not the main motivation behind this ID.
We think that during the CCAMP WG meeting, somehow everyone was commenting on the practically of the ERO counterpart. But as Zafar also mentioned in the question answer session that it is unfair to discuss merit and fate of this ID based on the ERO extensions contained herein.
In the light of the above, we would like the WG to discuss the ID based on its merit and applicably to resource recording in a network containing bundled TE link. Clearly, the proposed RRO extensions are a useful tool for administrative purpose.
N.B. We have also updated the ID, based on comments during last Ccamp WG meeting; An updated copy will be available at IETF Web site in a couple of days. In the mean time, a mirror version of the ID can be viewed at, http://psg.com/~dpapadimitriou/draft-zamfir-explicit-resource-control-bundle-02.txt.
Comments on usefulness on Component Link Recording for TE Link Bundles will be very much appreciated.
Zafar Ali, Ph. D. 100 South Main St. #200,
Technical Leader, Ann Arbor, MI 48104, USA.
Cisco Systems. (734) 276-2459.