Network Working Group                                        R. Aggarwal
Internet Draft                                          Juniper Networks
Expiration Date: May 2008
                                                             K. Kompella
                                                        Juniper Networks

                                                               T. Nadeau
                                                                      BT

                                                              G. Swallow
                                                     Cisco Systems, Inc.

                                                           November 2007


                           BFD For MPLS LSPs


                       draft-ietf-bfd-mpls-05.txt

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Raggarwa                                                        [Page 1]

Internet Draft         draft-ietf-bfd-mpls-05.txt          November 2007


Abstract

   One desirable application of Bi-directional Forwarding Detection
   (BFD) is to detect a MPLS LSP data plane failure. LSP-Ping is an
   existing mechanism for detecting MPLS data plane failures and for
   verifying the MPLS LSP data plane against the control plane. BFD can
   be used for the former, but not for the latter. However the control
   plane processing required for BFD control packets is relatively
   smaller than the processing required for LSP-Ping messages. A
   combination of LSP-Ping and BFD can be used to provide faster data
   plane failure detection and/or make it possible to provide such
   detection on a greater number of LSPs. This document describes the
   applicability of BFD in relation to LSP-Ping for this application. It
   also describes procedures for using BFD in this environment.



Table of Contents

 1          Specification of requirements  .........................   3
 2          Introduction  ..........................................   3
 3          Applicability  .........................................   3
 3.1        BFD for MPLS LSPs: Motivation  .........................   3
 3.2        Using BFD in Conjunction with LSP-Ping  ................   5
 4          Theory of Operation  ...................................