{
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  "sourcePath": "src/main/data/docs",
  "docId": "RFC8491",
  "document": {
    "abstract": "This document defines a way for an Intermediate System to Intermediate System (IS-IS) router to advertise multiple types of supported Maximum SID Depths (MSDs) at node and/or link granularity. Such advertisements allow entities (e.g., centralized controllers) to determine whether a particular Segment ID (SID) stack can be supported in a given network. This document only defines one type of MSD: Base MPLS Imposition. However, it defines an encoding that can support other MSD types. This document focuses on MSD use in a network that is Segment Routing (SR) enabled, but MSD may also be useful when SR is not enabled.",
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    "authors": [
      {
        "name": "Jeff Tantsura"
      },
      {
        "name": "Uma Chunduri"
      },
      {
        "name": "Sam Aldrin"
      },
      {
        "name": "Les Ginsberg"
      }
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    "docNumber": "8491",
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      "confidence": "high",
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      "updated": "2026-10-21T16:58:01.896Z",
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    "docTitle": "Signaling Maximum SID Depth (MSD) Using IS-IS",
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      "confidence": "high",
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    },
    "doi": "10.17487/RFC8491",
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      "confidence": "high",
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      "confidence": "high",
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      "updated": "2026-10-21T16:58:01.896Z",
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      "BGP-LS",
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      "confidence": "high",
      "note": "Parsed from RFC index XML keywords",
      "originalValue": null,
      "source": "parsed",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc8491/",
      "updated": "2026-10-21T16:58:01.896Z",
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    },
    "pages": "10",
    "pages$meta": {
      "confidence": "high",
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      "source": "parsed",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc8491/",
      "updated": "2026-10-21T16:58:01.896Z",
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    },
    "publicationDate": "2018-11-01",
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        "IETF.draft-ietf-isis-mpls-elc-06",
        "IETF.draft-ietf-idr-bgp-ls-segment-routing-msd-02",
        "IETF.draft-ietf-pce-segment-routing-13",
        "RFC7752"
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      "bibliographic$meta": {
        "confidence": "medium",
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        "note": "Parsed from RFC HTML references/informative sections",
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        "version": "extractDocs.js@commit:2c1e5418e9d0"
      },
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        "RFC2119",
        "RFC3031",
        "RFC7370",
        "RFC7981",
        "RFC8126",
        "RFC8174",
        "RFC8402"
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        "confidence": "high",
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    "status": {
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        "source": "resolved",
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        "confidence": "high",
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        "source": "parsed",
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      "latestVersion": true,
      "latestVersion$meta": {
        "confidence": "high",
        "note": "Derived from supersession relationship fields",
        "originalValue": null,
        "source": "resolved",
        "sourceUrl": "https://www.rfc-editor.org/info/rfc8491/",
        "updated": "2026-10-21T16:58:01.896Z",
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      "statusNote": "Proposed Standard",
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        "confidence": "high",
        "note": "Mapped from Datatracker doc.json std_level",
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        "source": "parsed",
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