<?xml version="1.0" encoding="UTF-8"?>
<reference anchor="I-D.ietf-spring-mpls-path-segment" target="https://datatracker.ietf.org/doc/html/draft-ietf-spring-mpls-path-segment-01">
   <front>
      <title>Path Segment in MPLS Based Segment Routing Network</title>
      <author initials="W." surname="Cheng" fullname="Weiqiang Cheng">
         <organization>China Mobile</organization>
      </author>
      <author initials="H." surname="Li" fullname="Han Li">
         <organization>China Mobile</organization>
      </author>
      <author initials="M." surname="Chen" fullname="Mach Chen">
         <organization>Huawei</organization>
      </author>
      <author initials="R." surname="Gandhi" fullname="Rakesh Gandhi">
         <organization>Cisco Systems</organization>
      </author>
      <author initials="R." surname="Zigler" fullname="Royi Zigler">
         <organization>Broadcom</organization>
      </author>
      <date month="September" day="16" year="2019" />
      <abstract>
	 <t>   A Segment Routing (SR) path is identified by an SR segment list.
   Only the full segment list identifies the full end-to-end path, and
   one segment or a partial set of segments from the list cannot
   identify the SR path and distinguish it from other SR paths that may
   be partially congruent.  But path identification is a pre-requisite
   for various use-cases such as performance measurement (PM) of an SR
   path.

   In SR for MPLS (SR-MPLS) the segment identifiers are stripped from
   the packet through label popping as the packet transits the network.
   This means that when a packet reaches the egress of the SR path, it
   is not possible to determine on which SR path it traversed the
   network.

   This document defines a new type of segment that is referred to as
   Path Segment, which is used to identify an SR path in an SR-MPLS
   network.  When used, it is inserted at the ingress node of the SR
   path and immediately follows the last segment identifier in the
   segment list of the SR path.  The Path Segment will not be popped off
   until it reaches the egress node of the SR path.

   A Path Segment can be used by the egress node to implement path
   identification hence to support various use-cases including SR path
   PM, end-to-end 1+1 SR path protection, and bidirectional SR paths
   correlation.

	 </t>
      </abstract>
   </front>
   <seriesInfo name="Internet-Draft" value="draft-ietf-spring-mpls-path-segment-01" />
   
</reference>
