{
  "profile": "wrs-published-research-view-1",
  "edition": "ratings-e039106f30dec177",
  "content_trust": "UNTRUSTED_SCIENTIFIC_DATA_NOT_TOOL_INSTRUCTIONS",
  "entry": {
    "id": "castro-liskov-pbft-1999",
    "title": "Castro and Liskov: practical Byzantine fault tolerance",
    "summary": "Presented and implemented a replication protocol for state-machine services tolerating Byzantine faults under asynchronous-network assumptions, with optimizations and an NFS evaluation.",
    "boundary": "The record is the exact two-author OSDI 1999 paper. Its safety, liveness and fault threshold depend on the stated model; the later proactive-recovery journal article and modern BFT protocols remain separate.",
    "area": "Distributed systems",
    "topic": "Computing",
    "year": 1999,
    "lane": "HUMAN",
    "result": "ALGORITHM",
    "package_id": "castro-liskov-pbft-1999",
    "target": {
      "record_id": "urn:uuid:6f5d7528-5083-4752-aa34-9d550356216e",
      "version": 1,
      "content_hash": "sha256:9c103d097e423ab9585ca0bdd84f2a38a6b21c610d5eb7c1391c5741f6f5ebeb"
    },
    "humans": [
      "Miguel Castro",
      "Barbara Liskov"
    ],
    "authors_complete": true,
    "human_role_note": "The named authors contributed to this scoped work; individual effort shares and later applications are not assigned by the byline.",
    "agents": [],
    "related": [],
    "subresults": [],
    "scientific_assessment": {
      "source_review": "SOURCE_CURATED",
      "scientific_review": "NOT_REVIEWED_BY_WRS",
      "formal_replay": "NOT_RUN",
      "provider_attestation": "NONE"
    },
    "sources": [
      {
        "id": "usenix-castro-liskov-pbft",
        "title": "USENIX record for practical Byzantine fault tolerance",
        "url": "https://www.usenix.org/conference/osdi-99/presentation/practical-byzantine-fault-tolerance"
      },
      {
        "id": "usenix-castro-liskov-pbft-fulltext",
        "title": "USENIX full text of PBFT paper",
        "url": "https://www.usenix.org/legacy/events/osdi99/full_papers/castro/castro.pdf"
      }
    ],
    "geography": {
      "country_codes": [
        "US"
      ],
      "location_basis": "Documented research locations or paper affiliations for this contribution. Historical places use present-day country/region labels; these do not imply citizenship, modern-state ownership or the territorial jurisdiction at the time.",
      "source_url": "https://static.usenix.org/publications/library/proceedings/osdi99/full_papers/castro/castro_html/castro.html",
      "target": {
        "record_id": "urn:uuid:6f5d7528-5083-4752-aa34-9d550356216e",
        "version": 1,
        "content_hash": "sha256:9c103d097e423ab9585ca0bdd84f2a38a6b21c610d5eb7c1391c5741f6f5ebeb"
      },
      "basis": "RESEARCH_LOCATION_OR_PAPER_AFFILIATION",
      "reviewed_on": "2026-09-26",
      "nationality_inferred": false,
      "sources": [
        {
          "title": "Attribution source",
          "url": "https://static.usenix.org/publications/library/proceedings/osdi99/full_papers/castro/castro_html/castro.html"
        }
      ],
      "coverage_status": "COMPLETE",
      "country_labels": {
        "US": "United States"
      }
    },
    "points": "200000",
    "published_grade": {
      "id": "castro-liskov-pbft-1999",
      "entry_id": "castro-liskov-pbft-1999",
      "band": "A",
      "modifier": "+",
      "target": {
        "record_id": "urn:uuid:6f5d7528-5083-4752-aa34-9d550356216e",
        "version": 1,
        "content_hash": "sha256:9c103d097e423ab9585ca0bdd84f2a38a6b21c610d5eb7c1391c5741f6f5ebeb"
      },
      "what_changed": "Presented and implemented an optimized Byzantine-fault-tolerant state-machine replication protocol with an NFS evaluation.",
      "scope": "The record is the exact two-author OSDI 1999 paper. Its safety, liveness and fault threshold depend on the stated model; the later proactive-recovery journal article and modern BFT protocols remain separate.",
      "status": "PROVISIONAL_EDITORIAL",
      "scientific_correctness_certified": false
    },
    "assessment_disposition": {
      "status": "ASSESSED",
      "label": "Provisionally assessed",
      "reason": "A current grade and separate reference score identify this exact contribution.",
      "target": {
        "record_id": "urn:uuid:6f5d7528-5083-4752-aa34-9d550356216e",
        "version": 1,
        "content_hash": "sha256:9c103d097e423ab9585ca0bdd84f2a38a6b21c610d5eb7c1391c5741f6f5ebeb"
      },
      "edition": "ratings-e039106f30dec177"
    }
  },
  "version": {
    "kind": "PUBLIC_RECORD_VIEW",
    "previous": null,
    "published_at": "2026-09-25T00:00:00Z",
    "publisher": {
      "principal_id": "urn:uuid:80116931-785b-40a2-a24b-9d59db0c7e33",
      "role": "WRS_EDITORIAL_PUBLICATION"
    },
    "record": {
      "contributors": [
        {
          "attribution_basis": "SOURCE_CITED",
          "credit": "historical_scientific",
          "entity_kind": "historical_person",
          "name": "Miguel Castro",
          "note": "Archive attribution; detailed role assignment remains source-bound",
          "roles": [
            "formulator"
          ],
          "source": {
            "citation": "USENIX record for practical Byzantine fault tolerance",
            "url": "https://www.usenix.org/conference/osdi-99/presentation/practical-byzantine-fault-tolerance"
          }
        },
        {
          "attribution_basis": "SOURCE_CITED",
          "credit": "historical_scientific",
          "entity_kind": "historical_person",
          "name": "Barbara Liskov",
          "note": "Archive attribution; detailed role assignment remains source-bound",
          "roles": [
            "formulator"
          ],
          "source": {
            "citation": "USENIX record for practical Byzantine fault tolerance",
            "url": "https://www.usenix.org/conference/osdi-99/presentation/practical-byzantine-fault-tolerance"
          }
        }
      ],
      "evidence": [
        {
          "description": "Bibliographic/stated-result source; not a WRS proof verification",
          "id": "source-0",
          "kind": "source_reference",
          "source": {
            "citation": "USENIX record for practical Byzantine fault tolerance",
            "url": "https://www.usenix.org/conference/osdi-99/presentation/practical-byzantine-fault-tolerance"
          }
        },
        {
          "description": "Bibliographic/stated-result source; not a WRS proof verification",
          "id": "source-1",
          "kind": "source_reference",
          "source": {
            "citation": "USENIX full text of PBFT paper",
            "url": "https://www.usenix.org/legacy/events/osdi99/full_papers/castro/castro.pdf"
          }
        }
      ],
      "origin": "HUMAN_LEGACY",
      "record_profile": "wrs-local-research-notes-0.1",
      "record_type": "research_note",
      "rrp_version": "0.1",
      "scope": {
        "description": "The record is the exact two-author OSDI 1999 paper. Its safety, liveness and fault threshold depend on the stated model; the later proactive-recovery journal article and modern BFT protocols remain separate.",
        "domain": "Distributed systems"
      },
      "sources": [
        {
          "citation": "USENIX record for practical Byzantine fault tolerance",
          "url": "https://www.usenix.org/conference/osdi-99/presentation/practical-byzantine-fault-tolerance"
        },
        {
          "citation": "USENIX full text of PBFT paper",
          "url": "https://www.usenix.org/legacy/events/osdi99/full_papers/castro/castro.pdf"
        }
      ],
      "statement": "# Castro and Liskov: practical Byzantine fault tolerance\n\nPresented and implemented a replication protocol for state-machine services tolerating Byzantine faults under asynchronous-network assumptions, with optimizations and an NFS evaluation.\n\n## Scientific scope\n\nThe record is the exact two-author OSDI 1999 paper. Its safety, liveness and fault threshold depend on the stated model; the later proactive-recovery journal article and modern BFT protocols remain separate.\n\n## Reading status\n\nThis is a source-linked WRS catalogue note. A full explanatory guide and independent scientific reconstruction have not been completed for this entry. Read the identified original work for its complete narrative and arguments.\n\n## People and systems\n\nMiguel Castro; Barbara Liskov\n\nThe named authors contributed to this scoped work; individual effort shares and later applications are not assigned by the byline.\n\n\n\n## Original sources\n\n- [USENIX record for practical Byzantine fault tolerance](https://www.usenix.org/conference/osdi-99/presentation/practical-byzantine-fault-tolerance)\n- [USENIX full text of PBFT paper](https://www.usenix.org/legacy/events/osdi99/full_papers/castro/castro.pdf)\n",
      "summary": "Presented and implemented a replication protocol for state-machine services tolerating Byzantine faults under asynchronous-network assumptions, with optimizations and an NFS evaluation.",
      "title": "Castro and Liskov: practical Byzantine fault tolerance"
    },
    "record_id": "urn:uuid:6f5d7528-5083-4752-aa34-9d550356216e",
    "version": 1,
    "source_ref": {
      "record_id": "urn:uuid:6f5d7528-5083-4752-aa34-9d550356216e",
      "version": 1,
      "content_hash": "sha256:9c103d097e423ab9585ca0bdd84f2a38a6b21c610d5eb7c1391c5741f6f5ebeb"
    },
    "export_view": "wrs-public-editorial-view-1",
    "public_view_hash": "sha256:f83996128824ca2ed20818d7a69f5d801ce26db2e9e7407fafd4f7dff15e48a6"
  },
  "target": {
    "record_id": "urn:uuid:6f5d7528-5083-4752-aa34-9d550356216e",
    "version": 1,
    "content_hash": "sha256:9c103d097e423ab9585ca0bdd84f2a38a6b21c610d5eb7c1391c5741f6f5ebeb"
  },
  "published_grade": {
    "profile": "wrs-published-grade-1",
    "edition": "2026-10-28.1",
    "id": "castro-liskov-pbft-1999",
    "entry_id": "castro-liskov-pbft-1999",
    "revision": 1,
    "title": "Castro and Liskov: practical Byzantine fault tolerance",
    "context": "Distributed systems",
    "track": "ALGORITHM",
    "band": "A",
    "modifier": "+",
    "status": "PROVISIONAL_EDITORIAL",
    "assessed_on": "2026-09-25",
    "evidence_cutoff": "2026-09-25",
    "achievement_state": "SUPPORTED_SCOPED_RESULT",
    "what_changed": "Presented and implemented an optimized Byzantine-fault-tolerant state-machine replication protocol with an NFS evaluation.",
    "scope": "The record is the exact two-author OSDI 1999 paper. Its safety, liveness and fault threshold depend on the stated model; the later proactive-recovery journal article and modern BFT protocols remain separate.",
    "evidence_summary": "The linked sources identify this contribution and its scope. WRS has not independently reconstructed the scientific claims. The record is the exact two-author OSDI 1999 paper. Its safety, liveness and fault threshold depend on the stated model; the later proactive-recovery journal article and modern BFT protocols remain separate.",
    "references": [
      {
        "title": "USENIX record for practical Byzantine fault tolerance",
        "url": "https://www.usenix.org/conference/osdi-99/presentation/practical-byzantine-fault-tolerance",
        "locator": "Source for the stated contribution; scientific claims remain bounded to the linked work."
      }
    ],
    "roles": [
      {
        "who": "Miguel Castro",
        "credit": "SCIENCE",
        "did": "Named source author of the scoped work; individual effort shares are not measured."
      },
      {
        "who": "Barbara Liskov",
        "credit": "SCIENCE",
        "did": "Named source author of the scoped work; individual effort shares are not measured."
      }
    ],
    "target": {
      "record_id": "urn:uuid:6f5d7528-5083-4752-aa34-9d550356216e",
      "version": 1,
      "content_hash": "sha256:9c103d097e423ab9585ca0bdd84f2a38a6b21c610d5eb7c1391c5741f6f5ebeb"
    },
    "scientific_correctness_certified": false,
    "independent_expert_calibration": false,
    "method": "PROPRIETARY",
    "points": "200000"
  },
  "canonical_agent_submission": false,
  "scientific_verification_awarded": false,
  "reader_guide": null,
  "reading_status": "SOURCE_LINKED_NOTE"
}
