{
  "draft": "draft-ietf-spring-mpls-path-segment-22",
  "doc_id": "RFC9545",
  "title": "Path Segment Identifier in MPLS-Based Segment Routing Networks",
  "authors": [
    "W. Cheng, Ed.",
    "H. Li",
    "C. Li, Ed.",
    "R. Gandhi",
    "R. Zigler"
  ],
  "format": [
    "XML",
    "TEXT",
    "HTML",
    "PDF"
  ],
  "page_count": "11",
  "pub_status": "PROPOSED STANDARD",
  "status": "PROPOSED STANDARD",
  "source": "Source Packet Routing in Networking",
  "abstract": "A Segment Routing (SR) path is identified by an SR segment list. A subset of segments from the segment list cannot be leveraged to distinguish one SR path from another as they may be partially congruent. SR path identification is a prerequisite for various use cases such as performance measurement and end-to-end 1+1 path protection.\n\n In an SR over MPLS (SR-MPLS) data plane, an egress node cannot determine on which SR path a packet traversed the network from the label stack because the segment identifiers are removed from the label stack as the packet transits the network.\n\n This document defines a Path Segment Identifier (PSID) to identify an SR path on the egress node of the path.",
  "pub_date": "February 2024",
  "keywords": [
    "Performance Measurement",
    "Bidirectional SR Path",
    "End-to-End Path Protection",
    "SR Path Segment",
    "Path Segment"
  ],
  "obsoletes": [],
  "obsoleted_by": [],
  "updates": [],
  "updated_by": [],
  "see_also": [],
  "doi": "10.17487/RFC9545",
  "errata_url": null
}