{
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  "sourcePath": "src/main/data/docs",
  "docId": "RFC5939",
  "document": {
    "abstract": "The Session Description Protocol (SDP) was intended to describe multimedia sessions for the purposes of session announcement, session invitation, and other forms of multimedia session initiation. SDP was not intended to provide capability indication or capability negotiation; however, over the years, SDP has seen widespread adoption and as a result it has been gradually extended to provide limited support for these, notably in the form of the offer/answer model defined in RFC 3264. SDP does not define how to negotiate one or more alternative transport protocols (e.g., RTP profiles) or attributes. This makes it difficult to deploy new RTP profiles such as Secure RTP or RTP with RTCP-based feedback, negotiate use of different security keying mechanisms, etc. It also presents problems for some forms of media negotiation. The purpose of this document is to address these shortcomings by extending SDP with capability negotiation parameters and associated offer/answer procedures to use those parameters in a backwards compatible manner. The document defines a general SDP Capability Negotiation framework. It also specifies how to provide attributes and transport protocols as capabilities and negotiate them using the framework. Extensions for other types of capabilities (e.g., media types and media formats) may be provided in other documents. [STANDARDS-TRACK]",
    "abstract$meta": {
      "confidence": "high",
      "note": "Parsed from RFC index XML abstract",
      "originalValue": null,
      "source": "parsed",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
      "updated": "2026-10-13T18:23:05.922Z",
      "version": "extractDocs.js@commit:6d30695438dd"
    },
    "authors": [
      {
        "name": "Flemming Andreasen"
      }
    ],
    "authors$meta": {
      "confidence": "high",
      "note": "Parsed from Datatracker doc page article:author (profile full names)",
      "originalValue": null,
      "source": "parsed",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
      "updated": "2026-10-13T18:23:05.922Z",
      "version": "extractDocs.js@commit:6d30695438dd"
    },
    "docId": "RFC5939",
    "docId$meta": {
      "confidence": "high",
      "note": "Derived from RFC number or Datatracker identifier",
      "originalValue": null,
      "source": "resolved",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
      "updated": "2026-10-13T18:23:05.922Z",
      "version": "extractDocs.js@commit:6d30695438dd"
    },
    "docLabel": "IETF RFC 5939",
    "docLabel$meta": {
      "confidence": "high",
      "note": "Constructed from provider and document identifier",
      "originalValue": null,
      "source": "resolved",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
      "updated": "2026-10-13T18:23:05.922Z",
      "version": "extractDocs.js@commit:6d30695438dd"
    },
    "docNumber": "5939",
    "docNumber$meta": {
      "confidence": "high",
      "note": "Parsed from RFC info page report metadata",
      "originalValue": null,
      "source": "parsed",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
      "updated": "2026-10-13T18:23:05.922Z",
      "version": "extractDocs.js@commit:6d30695438dd"
    },
    "docTitle": "Session Description Protocol (SDP) Capability Negotiation",
    "docTitle$meta": {
      "confidence": "high",
      "note": "Parsed from RFC index XML title",
      "originalValue": null,
      "source": "parsed",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
      "updated": "2026-10-13T18:23:05.922Z",
      "version": "extractDocs.js@commit:6d30695438dd"
    },
    "docType": "Standard",
    "docType$meta": {
      "confidence": "high",
      "note": "Mapped from Datatracker std_level or RFC status text",
      "originalValue": null,
      "source": "parsed",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
      "updated": "2026-10-13T18:23:05.922Z",
      "version": "extractDocs.js@commit:6d30695438dd"
    },
    "doi": "10.17487/RFC5939",
    "doi$meta": {
      "confidence": "high",
      "note": "Parsed from RFC index XML doi",
      "originalValue": null,
      "source": "resolved",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
      "updated": "2026-10-13T18:23:05.922Z",
      "version": "extractDocs.js@commit:6d30695438dd"
    },
    "href": "https://doi.org/10.17487/RFC5939",
    "href$meta": {
      "confidence": "high",
      "note": "Derived from DOI (https://doi.org/<doi>)",
      "originalValue": null,
      "source": "resolved",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
      "updated": "2026-10-13T18:23:05.922Z",
      "version": "extractDocs.js@commit:6d30695438dd"
    },
    "keywords": [
      "Multimedia Session",
      "Session Announcement",
      "Session Invitation"
    ],
    "keywords$meta": {
      "confidence": "high",
      "note": "Parsed from RFC index XML keywords",
      "originalValue": null,
      "source": "parsed",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
      "updated": "2026-10-13T18:23:05.922Z",
      "version": "extractDocs.js@commit:6d30695438dd"
    },
    "pages": "77",
    "pages$meta": {
      "confidence": "high",
      "note": "Parsed from RFC index XML page-count",
      "originalValue": null,
      "source": "parsed",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
      "updated": "2026-10-13T18:23:05.922Z",
      "version": "extractDocs.js@commit:6d30695438dd"
    },
    "publicationDate": "2010-09-01",
    "publicationDate$meta": {
      "confidence": "high",
      "note": "Parsed from RFC index XML date",
      "originalValue": null,
      "source": "parsed",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
      "updated": "2026-10-13T18:23:05.922Z",
      "version": "extractDocs.js@commit:6d30695438dd"
    },
    "publisher": "IETF",
    "publisher$meta": {
      "confidence": "high",
      "note": "Static: provider",
      "originalValue": null,
      "source": "parsed",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
      "updated": "2026-10-13T18:23:05.922Z",
      "version": "extractDocs.js@commit:6d30695438dd"
    },
    "references": {
      "bibliographic": [
        "RFC3261",
        "RFC3312",
        "RFC3262",
        "RFC3407",
        "RFC3551",
        "RFC3711",
        "RFC3830",
        "RFC4145",
        "RFC4474",
        "RFC4567",
        "RFC4568",
        "RFC4585",
        "RFC4588",
        "RFC4756",
        "RFC5027",
        "RFC5124",
        "RFC5751",
        "RFC5763",
        "RFC5764",
        "RFC5888",
        "orphan/RFC5939/h:f4972765",
        "orphan/RFC5939/h:863398ce",
        "orphan/RFC5939/h:c1f2e2ec",
        "orphan/RFC5939/h:eb8b9978"
      ],
      "bibliographic$meta": {
        "confidence": "medium",
        "flag": "MIXED_REF_LAYOUT_RISK anchored=30 proseBlocks=35 skippedAnchorBlocks=32",
        "note": "Parsed from RFC HTML references/informative sections",
        "originalValue": [],
        "reviewRequired": true,
        "source": "parsed",
        "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
        "updated": "2026-10-13T18:23:05.922Z",
        "version": "extractDocs.js@commit:6d30695438dd"
      },
      "normative": [
        "RFC2119",
        "RFC3264",
        "RFC4566",
        "RFC5226",
        "RFC5234",
        "RFC5245"
      ],
      "normative$meta": {
        "confidence": "high",
        "note": "Parsed from RFC HTML normative references sections",
        "originalValue": [],
        "source": "parsed",
        "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
        "updated": "2026-10-13T18:23:05.922Z",
        "version": "extractDocs.js@commit:6d30695438dd"
      }
    },
    "resolvedHref": "https://www.rfc-editor.org/info/rfc5939/",
    "resolvedHref$meta": {
      "confidence": "high",
      "note": "Final URL resolved via URL redirect verification",
      "originalValue": null,
      "source": "resolved",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
      "updated": "2026-10-13T18:23:05.922Z",
      "version": "extractDocs.js@commit:6d30695438dd"
    },
    "status": {
      "active": true,
      "active$meta": {
        "confidence": "high",
        "note": "Derived from supersession relationship fields",
        "originalValue": null,
        "source": "resolved",
        "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
        "updated": "2026-10-13T18:23:05.922Z",
        "version": "extractDocs.js@commit:6d30695438dd"
      },
      "amendedBy": [
        "RFC6871"
      ],
      "amendedBy$meta": {
        "confidence": "high",
        "note": "Parsed from RFC index XML",
        "originalValue": [],
        "source": "parsed",
        "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
        "updated": "2026-10-13T18:23:05.922Z",
        "version": "extractDocs.js@commit:6d30695438dd"
      },
      "errataExist": true,
      "errataExist$meta": {
        "confidence": "high",
        "note": "Derived from presence of errata links on RFC/Datatracker pages",
        "originalValue": null,
        "source": "parsed",
        "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
        "updated": "2026-10-13T18:23:05.922Z",
        "version": "extractDocs.js@commit:6d30695438dd"
      },
      "errataUrl": [
        "https://www.rfc-editor.org/errata/rfc5939",
        "https://www.rfc-editor.org/errata_search.php?rfc=5939",
        "https://www.rfc-editor.org/rfc/inline-errata/rfc5939.html"
      ],
      "errataUrl$meta": {
        "confidence": "high",
        "note": "Parsed from errata links on RFC/Datatracker pages",
        "originalValue": [],
        "source": "parsed",
        "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
        "updated": "2026-10-13T18:23:05.922Z",
        "version": "extractDocs.js@commit:6d30695438dd"
      },
      "latestVersion": true,
      "latestVersion$meta": {
        "confidence": "high",
        "note": "Derived from supersession relationship fields",
        "originalValue": null,
        "source": "resolved",
        "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
        "updated": "2026-10-13T18:23:05.922Z",
        "version": "extractDocs.js@commit:6d30695438dd"
      },
      "statusNote": "Proposed Standard",
      "statusNote$meta": {
        "confidence": "high",
        "note": "Mapped from Datatracker doc.json std_level",
        "originalValue": null,
        "source": "parsed",
        "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
        "updated": "2026-10-13T18:23:05.922Z",
        "version": "extractDocs.js@commit:6d30695438dd"
      },
      "superseded": false,
      "superseded$meta": {
        "confidence": "high",
        "note": "Derived from supersession relationship fields",
        "originalValue": null,
        "source": "resolved",
        "sourceUrl": "https://www.rfc-editor.org/info/rfc5939/",
        "updated": "2026-10-13T18:23:05.922Z",
        "version": "extractDocs.js@commit:6d30695438dd"
      }
    }
  }
}