FAILURE MAP
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FA-7556 / Multiplexed protocols / Open access

Quic max data updates are monotonic · case 01

Quic max data updates are monotonic.

Verified by executionVariant 1 · 4 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The faulty implementation uses `new` for the quic-max-data-updates-are-monotonic decision.

VERIFIED REPAIR

Apply the explicit quic-max-data-updates-are-monotonic contract, including the tested boundary and negative cases.

Unsuccessful approach: The attempted repair uses `old+new` and still violates a separate fixture.

Case contract

Bounded offline decision model: quic max data updates are monotonic. Inputs are already validated protocol fields; the explicit fixtures define the supported policy, not a complete protocol implementation.

Why this case matters

This deterministic multiplexed protocols model isolates the quic-max-data-updates-are-monotonic policy at a network component boundary.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import ipaddress
import re
from urllib.parse import urlsplit, urljoin
N = 1
observations = []
def solve(old, new):
    return new
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
_fixtures = ["check('fixture 1', solve(10, 5), 10)", "check('fixture 2', solve(10, 20), 20)", "check('fixture 3', solve(0, 0), 0)", "check('fixture 4', solve(0, 5), 5)"]
for _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:
    exec(_line)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
fixture 22020Passed
fixture 300Passed
fixture 455Passed
fixture 1510Failed

SHA-256 / 2edd431b5b480393889034ccb7014ba256c030d5b94410b9cbed7dd7d3c8681f

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import ipaddress
import re
from urllib.parse import urlsplit, urljoin
N = 1
observations = []
def solve(old, new):
    return old+new
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
_fixtures = ["check('fixture 1', solve(10, 5), 10)", "check('fixture 2', solve(10, 20), 20)", "check('fixture 3', solve(0, 0), 0)", "check('fixture 4', solve(0, 5), 5)"]
for _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:
    exec(_line)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
fixture 23020Failed
fixture 300Passed
fixture 455Passed
fixture 11510Failed

SHA-256 / 9787995813eb7672776e8731e0b7faf9ba389a3b46434039b387b66c9354237c

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json
import ipaddress
import re
from urllib.parse import urlsplit, urljoin
N = 1
observations = []
def solve(old, new):
    return max(old,new)
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
_fixtures = ["check('fixture 1', solve(10, 5), 10)", "check('fixture 2', solve(10, 20), 20)", "check('fixture 3', solve(0, 0), 0)", "check('fixture 4', solve(0, 5), 5)"]
for _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:
    exec(_line)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
fixture 22020Passed
fixture 300Passed
fixture 455Passed
fixture 11010Passed

SHA-256 / ae3091ffed4a5e35ec9680b661b3453084fe665b050bd1665271fbe431618774

Verification & scope

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.

Observations recorded using Python 3.12.14 at 2026-09-29T14:38:13.170320+00:00.

Case digest / b4187eabb8b93732e07512da4d062ad43ca7e160d2a38b4772de166598482568