The run did not exercise this test: ECN validation failed: packets sent marked ECT(0) came back acknowledged without ECN counts, so the marking was disabled. Whether the peer declined to report or the path rewrote the codepoint cannot be told apart from this end.
The suite could not establish what this client does here. That is a shortcoming of the run rather than anything about the client, and every one of these is on our list to remove.
What was measured
- Client
- aioquic — aioquic, 1.3.0 (PyPI wheel)
- Test
- Packets marked ECT(0) —
q-ecn - Clause
- RFC 9000 §13.4 (MUST)
- Class
- correctness — Rejected something invalid, with the code the RFC names.
- Required behaviour
- Echo the ECN counts back in ACK frames carrying an ECN section (type 0x03). §13.4.1 makes this a conditional requirement — an endpoint MUST report the markings it receives "if these are accessible", and explicitly permits an endpoint with no access to the ECN field to report nothing. So counts coming back is a pass, and silence is inconclusive rather than a failure: it cannot be told apart from a path that stripped the codepoint in transit.
- Measured
- 2026-09-19
Reproduce it
The suite is the judge, so the reproduction is to point the same client at the same test and let the server report what it saw.
SESSION=$(curl -sX POST https://conformance.pqcrypta.com/session | jq -r .id)
# then drive aioquic at the test URL and read the verdict:
curl -s https://conformance.pqcrypta.com/report/$SESSION.json | jq '.results["q-ecn"]'