{
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  "sourcePath": "src/main/data/docs",
  "docId": "RFC7821",
  "document": {
    "abstract": "The Network Time Protocol (NTP) allows clients to synchronize to a time server using timestamped protocol messages. To facilitate accurate timestamping, some implementations use hardware-based timestamping engines that integrate the accurate transmission time into every outgoing NTP packet during transmission. Since these packets are transported over UDP, the UDP Checksum field is then updated to reflect this modification. This document proposes an extension field that includes a 2-octet Checksum Complement, allowing timestamping engines to reflect the checksum modification in the last 2 octets of the packet rather than in the UDP Checksum field. The behavior defined in this document is interoperable with existing NTP implementations.",
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      "sourceUrl": "https://www.rfc-editor.org/info/rfc7821/",
      "updated": "2026-10-15T19:19:31.322Z",
      "version": "extractDocs.js@commit:669b9e3c6fef"
    },
    "authors": [
      {
        "name": "Tal Mizrahi"
      }
    ],
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      "confidence": "high",
      "note": "Parsed from Datatracker doc page article:author (profile full names)",
      "originalValue": null,
      "source": "parsed",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc7821/",
      "updated": "2026-10-15T19:19:31.322Z",
      "version": "extractDocs.js@commit:669b9e3c6fef"
    },
    "docId": "RFC7821",
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      "confidence": "high",
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      "originalValue": null,
      "source": "resolved",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc7821/",
      "updated": "2026-10-15T19:19:31.322Z",
      "version": "extractDocs.js@commit:669b9e3c6fef"
    },
    "docLabel": "IETF RFC 7821",
    "docLabel$meta": {
      "confidence": "high",
      "note": "Constructed from provider and document identifier",
      "originalValue": null,
      "source": "resolved",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc7821/",
      "updated": "2026-10-15T19:19:31.322Z",
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    },
    "docNumber": "7821",
    "docNumber$meta": {
      "confidence": "high",
      "note": "Parsed from RFC info page report metadata",
      "originalValue": null,
      "source": "parsed",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc7821/",
      "updated": "2026-10-15T19:19:31.322Z",
      "version": "extractDocs.js@commit:669b9e3c6fef"
    },
    "docTitle": "UDP Checksum Complement in the Network Time Protocol (NTP)",
    "docTitle$meta": {
      "confidence": "high",
      "note": "Parsed from RFC index XML title",
      "originalValue": null,
      "source": "parsed",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc7821/",
      "updated": "2026-10-15T19:19:31.322Z",
      "version": "extractDocs.js@commit:669b9e3c6fef"
    },
    "docType": "Experimental",
    "docType$meta": {
      "confidence": "high",
      "note": "Mapped from Datatracker std_level or RFC status text",
      "originalValue": null,
      "source": "parsed",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc7821/",
      "updated": "2026-10-15T19:19:31.322Z",
      "version": "extractDocs.js@commit:669b9e3c6fef"
    },
    "doi": "10.17487/RFC7821",
    "doi$meta": {
      "confidence": "high",
      "note": "Parsed from RFC index XML doi",
      "originalValue": null,
      "source": "resolved",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc7821/",
      "updated": "2026-10-15T19:19:31.322Z",
      "version": "extractDocs.js@commit:669b9e3c6fef"
    },
    "href": "https://doi.org/10.17487/RFC7821",
    "href$meta": {
      "confidence": "high",
      "note": "Derived from DOI (https://doi.org/<doi>)",
      "originalValue": null,
      "source": "resolved",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc7821/",
      "updated": "2026-10-15T19:19:31.322Z",
      "version": "extractDocs.js@commit:669b9e3c6fef"
    },
    "keywords": [
      "NTP",
      "UDP",
      "Checksum",
      "Timestamping"
    ],
    "keywords$meta": {
      "confidence": "high",
      "note": "Parsed from RFC index XML keywords",
      "originalValue": null,
      "source": "parsed",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc7821/",
      "updated": "2026-10-15T19:19:31.322Z",
      "version": "extractDocs.js@commit:669b9e3c6fef"
    },
    "pages": "14",
    "pages$meta": {
      "confidence": "high",
      "note": "Parsed from RFC index XML page-count",
      "originalValue": null,
      "source": "parsed",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc7821/",
      "updated": "2026-10-15T19:19:31.322Z",
      "version": "extractDocs.js@commit:669b9e3c6fef"
    },
    "publicationDate": "2016-03-01",
    "publicationDate$meta": {
      "confidence": "high",
      "note": "Parsed from RFC index XML date",
      "originalValue": null,
      "source": "parsed",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc7821/",
      "updated": "2026-10-15T19:19:31.322Z",
      "version": "extractDocs.js@commit:669b9e3c6fef"
    },
    "publisher": "IETF",
    "publisher$meta": {
      "confidence": "high",
      "note": "Static: provider",
      "originalValue": null,
      "source": "parsed",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc7821/",
      "updated": "2026-10-15T19:19:31.322Z",
      "version": "extractDocs.js@commit:669b9e3c6fef"
    },
    "references": {
      "bibliographic": [
        "10.1109-IEEESTD.2008.4579760",
        "RFC7820",
        "RFC7384",
        "RFC6936"
      ],
      "bibliographic$meta": {
        "confidence": "medium",
        "flag": "MIXED_REF_LAYOUT_RISK anchored=11 proseBlocks=15 skippedAnchorBlocks=12",
        "note": "Parsed from RFC HTML references/informative sections",
        "originalValue": [],
        "reviewRequired": true,
        "source": "parsed",
        "sourceUrl": "https://www.rfc-editor.org/info/rfc7821/",
        "updated": "2026-10-15T19:19:31.323Z",
        "version": "extractDocs.js@commit:669b9e3c6fef"
      },
      "normative": [
        "RFC1624",
        "RFC2460",
        "RFC2119",
        "RFC5905",
        "RFC7822",
        "RFC768"
      ],
      "normative$meta": {
        "confidence": "high",
        "note": "Parsed from RFC HTML normative references sections",
        "originalValue": [],
        "source": "parsed",
        "sourceUrl": "https://www.rfc-editor.org/info/rfc7821/",
        "updated": "2026-10-15T19:19:31.323Z",
        "version": "extractDocs.js@commit:669b9e3c6fef"
      }
    },
    "resolvedHref": "https://www.rfc-editor.org/info/rfc7821/",
    "resolvedHref$meta": {
      "confidence": "high",
      "note": "Final URL resolved via URL redirect verification",
      "originalValue": null,
      "source": "resolved",
      "sourceUrl": "https://www.rfc-editor.org/info/rfc7821/",
      "updated": "2026-10-15T19:19:31.322Z",
      "version": "extractDocs.js@commit:669b9e3c6fef"
    },
    "status": {
      "active": true,
      "active$meta": {
        "confidence": "high",
        "note": "Derived from supersession relationship fields",
        "originalValue": null,
        "source": "resolved",
        "sourceUrl": "https://www.rfc-editor.org/info/rfc7821/",
        "updated": "2026-10-15T19:19:31.322Z",
        "version": "extractDocs.js@commit:669b9e3c6fef"
      },
      "amendedBy": [
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      "amendedBy$meta": {
        "confidence": "high",
        "note": "Parsed from RFC index XML",
        "originalValue": [],
        "source": "parsed",
        "sourceUrl": "https://www.rfc-editor.org/info/rfc7821/",
        "updated": "2026-10-15T19:19:31.323Z",
        "version": "extractDocs.js@commit:669b9e3c6fef"
      },
      "errataExist": false,
      "errataExist$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/rfc7821/",
        "updated": "2026-10-15T19:19:31.323Z",
        "version": "extractDocs.js@commit:669b9e3c6fef"
      },
      "latestVersion": true,
      "latestVersion$meta": {
        "confidence": "high",
        "note": "Derived from supersession relationship fields",
        "originalValue": null,
        "source": "resolved",
        "sourceUrl": "https://www.rfc-editor.org/info/rfc7821/",
        "updated": "2026-10-15T19:19:31.322Z",
        "version": "extractDocs.js@commit:669b9e3c6fef"
      },
      "statusNote": "Experimental",
      "statusNote$meta": {
        "confidence": "high",
        "note": "Mapped from Datatracker doc.json std_level",
        "originalValue": null,
        "source": "parsed",
        "sourceUrl": "https://www.rfc-editor.org/info/rfc7821/",
        "updated": "2026-10-15T19:19:31.322Z",
        "version": "extractDocs.js@commit:669b9e3c6fef"
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      "superseded": false,
      "superseded$meta": {
        "confidence": "high",
        "note": "Derived from supersession relationship fields",
        "originalValue": null,
        "source": "resolved",
        "sourceUrl": "https://www.rfc-editor.org/info/rfc7821/",
        "updated": "2026-10-15T19:19:31.322Z",
        "version": "extractDocs.js@commit:669b9e3c6fef"
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}