{"abstract":"Dns ttl is reduced by resident seconds and clamped.","category":"DNS resolution","checks":4,"contract":"Given records, elapsed, dns ttl is reduced by resident seconds and clamped. Return the protocol decision or transformed value; fields are validated and fixtures state boundary outcomes.","evaluation_group":"xh-dns-ttl-is-reduced-by-resident-seconds-and-clamped","failed_approach":"The attempted repair uses `[(value,max(0,ttl-elapsed)) for value,ttl in records]` and still violates a separate fixture.","family":"xh-dns-ttl-is-reduced-by-resident-seconds-and-clamped","id":"FA-7361","implementations":{"attempt":{"sha256":"43261b2808069a9d5608e5bfbe43580df6444dd2aa0256451a17a30af4aaab11","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(records, elapsed):\n    return [(value,max(0,ttl-elapsed)) for value,ttl in records]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\n_fixtures = [\"check('fixture 1', solve([('a', 10), ('b', 30)], 10), [('b', 20)])\", \"check('fixture 2', solve([], 3), [])\", \"check('fixture 3', solve([('a', 0)], 0), [])\", \"check('fixture 4', solve([('a', 10)], 3), [('a', 7)])\"]\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":"93f19c45256f9165cf3193a65a40cdcaf0e379b29b70ab967f84e26786f8fbb2","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(records, elapsed):\n    return records\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\n_fixtures = [\"check('fixture 1', solve([('a', 10), ('b', 30)], 10), [('b', 20)])\", \"check('fixture 2', solve([], 3), [])\", \"check('fixture 3', solve([('a', 0)], 0), [])\", \"check('fixture 4', solve([('a', 10)], 3), [('a', 7)])\"]\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":"da4e4684080a37a0d06f454161d9c36d8162c27a931104d001ad1fab12240549","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(records, elapsed):\n    return [(value,max(0,ttl-elapsed)) for value,ttl in records if ttl > elapsed]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\n_fixtures = [\"check('fixture 1', solve([('a', 10), ('b', 30)], 10), [('b', 20)])\", \"check('fixture 2', solve([], 3), [])\", \"check('fixture 3', solve([('a', 0)], 0), [])\", \"check('fixture 4', solve([('a', 10)], 3), [('a', 7)])\"]\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-dns-ttl-is-reduced-by-resident-seconds-and-clamped","generated_at":"2026-09-29T14:38:11.094768+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"This deterministic dns resolution model isolates the dns-ttl-is-reduced-by-resident-seconds-and-clamped policy at a network component boundary.","repair":"Apply the explicit dns-ttl-is-reduced-by-resident-seconds-and-clamped contract, including the tested boundary and negative cases.","root_cause":"The faulty implementation uses `records` for the dns-ttl-is-reduced-by-resident-seconds-and-clamped decision.","sha256":"ba1cbbf19540417564380ef2add25a28773991faf1cba3e07425e5b9767e6f2e","title":"Dns ttl is reduced by resident seconds and clamped · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":55.99,"exit_code":1,"observations":[{"actual":[],"check":"fixture 2","expected":[],"passed":true},{"actual":[["a",0]],"check":"fixture 3","expected":[],"passed":false},{"actual":[["a",7]],"check":"fixture 4","expected":[["a",7]],"passed":true},{"actual":[["a",0],["b",20]],"check":"fixture 1","expected":[["b",20]],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 2\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": [[\"a\", 0]], \"expected\": [], \"passed\": false}, {\"check\": \"fixture 4\", \"actual\": [[\"a\", 7]], \"expected\": [[\"a\", 7]], \"passed\": true}, {\"check\": \"fixture 1\", \"actual\": [[\"a\", 0], [\"b\", 20]], \"expected\": [[\"b\", 20]], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":55.782,"exit_code":1,"observations":[{"actual":[],"check":"fixture 2","expected":[],"passed":true},{"actual":[["a",0]],"check":"fixture 3","expected":[],"passed":false},{"actual":[["a",10]],"check":"fixture 4","expected":[["a",7]],"passed":false},{"actual":[["a",10],["b",30]],"check":"fixture 1","expected":[["b",20]],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 2\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": [[\"a\", 0]], \"expected\": [], \"passed\": false}, {\"check\": \"fixture 4\", \"actual\": [[\"a\", 10]], \"expected\": [[\"a\", 7]], \"passed\": false}, {\"check\": \"fixture 1\", \"actual\": [[\"a\", 10], [\"b\", 30]], \"expected\": [[\"b\", 20]], \"passed\": false}], \"passed\": false}\n"},"fixed":{"elapsed_ms":48.178,"exit_code":0,"observations":[{"actual":[],"check":"fixture 2","expected":[],"passed":true},{"actual":[],"check":"fixture 3","expected":[],"passed":true},{"actual":[["a",7]],"check":"fixture 4","expected":[["a",7]],"passed":true},{"actual":[["b",20]],"check":"fixture 1","expected":[["b",20]],"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 2\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [[\"a\", 7]], \"expected\": [[\"a\", 7]], \"passed\": true}, {\"check\": \"fixture 1\", \"actual\": [[\"b\", 20]], \"expected\": [[\"b\", 20]], \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}