Fwd: I-D Action: draft-bashandy-rtgwg-segment-routing-ti-lfa-03.txt

"Ahmed Bashandy (bashandy)" <bashandy@cisco.com> Wed, 28 March 2018 23:12 UTC

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Subject: Fwd: I-D Action: draft-bashandy-rtgwg-segment-routing-ti-lfa-03.txt
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From: "Ahmed Bashandy (bashandy)" <bashandy@cisco.com>
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This is a new version of the Ti-lfa draft. The key changes are:
- Added a section 6 that provides statistics on the number of SIDs 
needed to protect against link, node, and local SRLG
- Defined the term "topology independent"
- Confirmed near the beginning of Section 3 that the mechanisms in the 
document are applicable whether downstream routers have converged or 
not, thereby alleviating any need for co-ordination or message exchange 
between the PLR and any other router in the network
- At the end of Section 5, we added paragraphs to explain how a PLR is 
able to protect SR-policies by inspecting the SID right after the active 
SID and determining the correct action accordingly
- Addressed comments that were sent out on the rtgwg mailing list. If 
there is anything that is overlooked, we are more than happy to address 
and/or correct.

All comments are most welcomed


-------- Forwarded Message --------
Subject: 	I-D Action: draft-bashandy-rtgwg-segment-routing-ti-lfa-03.txt
Date: 	Wed, 28 Mar 2018 07:15:14 -0700
From: 	internet-drafts@ietf.org
Reply-To: 	internet-drafts@ietf.org
To: 	i-d-announce@ietf.org

A New Internet-Draft is available from the on-line Internet-Drafts directories.

         Title           : Topology Independent Fast Reroute using Segment Routing
         Authors         : Ahmed Bashandy
                           Clarence Filsfils
                           Bruno Decraene
                           Stephane Litkowski
                           Pierre Francois
                           Daniel Voyer
	Filename        : draft-bashandy-rtgwg-segment-routing-ti-lfa-03.txt
	Pages           : 18
	Date            : 2018-03-28

    This document presents Topology Independent Loop-free Alternate Fast
    Re-route (TI-LFA), aimed at providing protection of node and
    adjacency segments within the Segment Routing (SR) framework.  This
    Fast Re-route (FRR) behavior builds on proven IP-FRR concepts being
    LFAs, remote LFAs (RLFA), and remote LFAs with directed forwarding
    (DLFA).  It extends these concepts to provide guaranteed coverage in
    any IGP network.  A key aspect of TI-LFA is the FRR path selection
    approach establishing protection over post-convergence paths from
    the point of local repair, dramatically reducing the operational
    need to control the tie-breaks among various FRR options.

The IETF datatracker status page for this draft is:

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