{"abstract":"Syn sequence space is independent of payload.","category":"Transport flow control","checks":4,"contract":"Bounded offline decision model: syn sequence space is independent of payload. Inputs are already validated protocol fields; the explicit fixtures define the supported policy, not a complete protocol implementation.","evaluation_group":"xh-syn-sequence-space-is-independent-of-payload","failed_approach":"The attempted repair uses `payload+int(syn or fin)` and still violates a separate fixture.","family":"xh-syn-sequence-space-is-independent-of-payload","id":"FA-7226","implementations":{"attempt":{"sha256":"c5c34677ebdf679f35c7eb8ab04cf273df1e98303da530cd5923ecc41ad325d7","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport ipaddress\nimport re\nfrom urllib.parse import urlsplit, urljoin\nN = 1\nobservations = []\ndef solve(payload, syn, fin):\n    return payload+int(syn or fin)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\n_fixtures = [\"check('fixture 1', solve(0, True, False), 1)\", \"check('fixture 2', solve(2, True, True), 4)\", \"check('fixture 3', solve(2, False, False), 2)\", \"check('fixture 4', solve(0, False, True), 1)\"]\nfor _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:\n    exec(_line)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"broken":{"sha256":"73171b42ca70dd80a5597e008222392b492df3a7089732a39b3d576906f913bc","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport ipaddress\nimport re\nfrom urllib.parse import urlsplit, urljoin\nN = 1\nobservations = []\ndef solve(payload, syn, fin):\n    return payload+int(fin)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\n_fixtures = [\"check('fixture 1', solve(0, True, False), 1)\", \"check('fixture 2', solve(2, True, True), 4)\", \"check('fixture 3', solve(2, False, False), 2)\", \"check('fixture 4', solve(0, False, True), 1)\"]\nfor _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:\n    exec(_line)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"fixed":{"sha256":"ae020cfd9f0710f1b62813933fcdf11bea537a742b92f48313e806bd98c70957","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport ipaddress\nimport re\nfrom urllib.parse import urlsplit, urljoin\nN = 1\nobservations = []\ndef solve(payload, syn, fin):\n    return payload+int(syn)+int(fin)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\n_fixtures = [\"check('fixture 1', solve(0, True, False), 1)\", \"check('fixture 2', solve(2, True, True), 4)\", \"check('fixture 3', solve(2, False, False), 2)\", \"check('fixture 4', solve(0, False, True), 1)\"]\nfor _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:\n    exec(_line)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"}},"limitations":"Bounded deterministic policy model over validated inputs; not a complete protocol stack or an interoperability claim. The five variants rotate the same explicit fixture set. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.","method":"Deterministic executable model with adversarial boundary fixtures.","provenance":{"created_by":"Failure Map","dependencies":"Python standard library","family":"xh-syn-sequence-space-is-independent-of-payload","generated_at":"2026-09-29T14:38:09.617971+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"This deterministic transport flow control model isolates the syn-sequence-space-is-independent-of-payload policy at a network component boundary.","repair":"Apply the explicit syn-sequence-space-is-independent-of-payload contract, including the tested boundary and negative cases.","root_cause":"The faulty implementation uses `payload+int(fin)` for the syn-sequence-space-is-independent-of-payload decision.","sha256":"d486667503effb116cda900100eca16c689a0cd919147fcd5ce682605ff4a3a6","title":"Syn sequence space is independent of payload · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":43.995,"exit_code":1,"observations":[{"actual":3,"check":"fixture 2","expected":4,"passed":false},{"actual":2,"check":"fixture 3","expected":2,"passed":true},{"actual":1,"check":"fixture 4","expected":1,"passed":true},{"actual":1,"check":"fixture 1","expected":1,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 2\", \"actual\": 3, \"expected\": 4, \"passed\": false}, {\"check\": \"fixture 3\", \"actual\": 2, \"expected\": 2, \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": 1, \"expected\": 1, \"passed\": true}, {\"check\": \"fixture 1\", \"actual\": 1, \"expected\": 1, \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":44.391,"exit_code":1,"observations":[{"actual":3,"check":"fixture 2","expected":4,"passed":false},{"actual":2,"check":"fixture 3","expected":2,"passed":true},{"actual":1,"check":"fixture 4","expected":1,"passed":true},{"actual":0,"check":"fixture 1","expected":1,"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 2\", \"actual\": 3, \"expected\": 4, \"passed\": false}, {\"check\": \"fixture 3\", \"actual\": 2, \"expected\": 2, \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": 1, \"expected\": 1, \"passed\": true}, {\"check\": \"fixture 1\", \"actual\": 0, \"expected\": 1, \"passed\": false}], \"passed\": false}\n"},"fixed":{"elapsed_ms":43.618,"exit_code":0,"observations":[{"actual":4,"check":"fixture 2","expected":4,"passed":true},{"actual":2,"check":"fixture 3","expected":2,"passed":true},{"actual":1,"check":"fixture 4","expected":1,"passed":true},{"actual":1,"check":"fixture 1","expected":1,"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 2\", \"actual\": 4, \"expected\": 4, \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": 2, \"expected\": 2, \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": 1, \"expected\": 1, \"passed\": true}, {\"check\": \"fixture 1\", \"actual\": 1, \"expected\": 1, \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}