FA-7506 / Multiplexed protocols / Open access

Http2 ping requires zero stream and eight byte payload · case 01

Http2 ping requires zero stream and eight byte payload.

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

ROOT CAUSE

The faulty implementation uses `length == 8` for the http2-ping-requires-zero-stream-and-eight-byte-payload decision.

VERIFIED REPAIR

Apply the explicit http2-ping-requires-zero-stream-and-eight-byte-payload contract, including the tested boundary and negative cases.

Unsuccessful approach: The attempted repair uses `stream == 0` and still violates a separate fixture.

Case contract

Bounded offline decision model: http2 ping requires zero stream and eight byte payload. 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 http2-ping-requires-zero-stream-and-eight-byte-payload 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(stream, length):
    return length == 8
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
_fixtures = ["check('fixture 1', solve(1, 8), False)", "check('fixture 2', solve(0, 7), False)", "check('fixture 3', solve(0, 8), True)", "check('fixture 4', solve(1, 7), False)"]
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 fixture	Actual	Expected	Outcome
fixture 2	`False`	`False`	Passed
fixture 3	`True`	`True`	Passed
fixture 4	`False`	`False`	Passed
fixture 1	`True`	`False`	Failed

SHA-256 / 05e3ff5f401a2ac491e037323ecfe1aab4dd9b113aca096e5599d2b3d3583557

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(stream, length):
    return stream == 0
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
_fixtures = ["check('fixture 1', solve(1, 8), False)", "check('fixture 2', solve(0, 7), False)", "check('fixture 3', solve(0, 8), True)", "check('fixture 4', solve(1, 7), False)"]
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 fixture	Actual	Expected	Outcome
fixture 2	`True`	`False`	Failed
fixture 3	`True`	`True`	Passed
fixture 4	`False`	`False`	Passed
fixture 1	`False`	`False`	Passed

SHA-256 / 4cb5b633468b2d65812005b74feffd4f64fbca9ca321430cd9546b4b7d4589e2

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(stream, length):
    return stream == 0 and length == 8
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
_fixtures = ["check('fixture 1', solve(1, 8), False)", "check('fixture 2', solve(0, 7), False)", "check('fixture 3', solve(0, 8), True)", "check('fixture 4', solve(1, 7), False)"]
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 fixture	Actual	Expected	Outcome
fixture 2	`False`	`False`	Passed
fixture 3	`True`	`True`	Passed
fixture 4	`False`	`False`	Passed
fixture 1	`False`	`False`	Passed

SHA-256 / 80bf2548b605d2dbb9310f5c3db65612f1fbf1f361b9625c5fcd21a1f771bfac

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 2026-09-29T14:38:12.753949+00:00.

Case digest / 79961128e565b3ecdb017f78c494521a2339da007cd094a224ded87e0dded2a1