moxygen
Metafb.mvfst.net:9448/moq-relay
A deployment of Moxygen, operated by Meta. Everything below was measured on this deployment, at whatever version and configuration it was running — it is not a measurement of that codebase. About this endpoint
At a glance
- Identifies itself as
- Meta MoQ C++ Draft-14
- Protocols accepted
- moq-00, h3, moqt-16, moqt-18, moqt-22
- Media delivery
- delivered, first object 115ms
- Violations recorded
- 1
Certificate
- Subject
- CN=fb.mvfst.net
- Issuer
- C=US, O=Let's Encrypt, CN=YE1
- Valid until
- 2026-12-24 50 days left
- Trust
- Publicly trusted
- Verification
- Completed with the certificate verified
Control messages
Which control messages this endpoint answered, per draft. An error reply is still an answer — ok and err are both support; what is recorded as missing is a message that got no answer at all. A dash is neither: it means the exchange ended on our side, so nothing about this endpoint was measured there.
| Draft | SUBSCRIBE | FETCH | TRACK_STATUS | SUBSCRIBE_NAMESPACE | PUBLISH_NAMESPACE | SUBSCRIBE_TRACKS | PUBLISH |
|---|---|---|---|---|---|---|---|
| 22 QUIC | ✓ err | ✓ err | ✓ err | ✓ ok | ✓ ok | ✓ ok | ✓ ok |
| 18 QUIC | ✓ err | ✓ err | ✓ err | ✓ ok | ✓ ok | ✓ ok | ✓ ok |
| 16 QUIC | ✓ err | ✓ err | ✓ err | ✓ ok | ✓ ok | · | ✓ ok |
| 14 QUIC | ✓ err | ✓ err | ✓ err | ✓ ok | ✓ ok | · | ✓ ok |
Media delivery
One publisher and two subscribers, to see whether an object published through this endpoint reaches a client that asked for it.
- Objects delivered
- 7/7
- Groups / subgroups
- 2 / 3
- Subscribe answered
- 230ms
- First object
- 115ms
- Stream framing
- streams kept as sent
- Second subscriber
- Same object delivered to a second subscriber
- Offers a track
- relay offered nothing
Two publishers of one track
Two publishers announce the same namespace and publish the same tracks, one with identical payloads and one with payloads that differ by publisher. Partway through, the publisher serving the subscribers disconnects without notice. A fresh subscription, sent afterwards, shows whether the remaining publisher could still be reached.
| Publisher | Role | Announcement | Subscribed to | Ended by the relay |
|---|---|---|---|---|
| first publisher | cancelled The relay accepted it, then withdrew its namespace. | accepted, REQUEST_OK in 114 ms | — | Namespace withdrawn: stream reset (code 1) |
| second publisher disconnected | serving The relay accepted it and subscribed to it. | accepted, REQUEST_OK in 122 ms | identical payloads, differing payloads | — |
| Track | Objects | From | When the publisher left | Ended by |
|---|---|---|---|---|
| identical payloads | each object once 15 delivered | — | ended by the relay | PUBLISH_DONE 4294967295 “closed locally” |
| differing payloads | each object once 15 delivered | second publisher | ended by the relay | PUBLISH_DONE 4294967295 “closed locally” |
A fresh subscription after the publisher left: refused with REQUEST_ERROR 16 “no such namespace or track”.
Specification violations
One Track Alias must not be used for two tracks at once.
Draft 22 over QUIC, during the delivery run, asking the relay to offer a track
- Specification
- draft-ietf-moq-transport-22, Section 3.1.3
- Required response
- close the session with DUPLICATE_TRACK_ALIAS (0x5)
Setup parameters
What this endpoint sent back in its setup response, per draft. A parameter with no name is a code point the negotiated draft does not define.
draft 22 · QUIC
- 0x07 moqt_implementation = Meta MoQ C++ Draft-14
draft 18 · QUIC
- 0x07 moqt_implementation = Meta MoQ C++ Draft-14
draft 16 · QUIC
- 0x02 max_request_id = 100
- 0x04 max_auth_token_cache_size = 1024
- 0x07 moqt_implementation = Meta MoQ C++ Draft-14
draft 14 · QUIC
- 0x02 max_request_id = 100
- 0x04 max_auth_token_cache_size = 1024
- 0x07 not defined by this draft = Meta MoQ C++ Draft-14 (moqt_implementation in 15–23)
History
9 sweeps, newest first. A step where the probe build or the measuring location changed is marked, and is not read as a change of the relay.
27 Oct 2026 → 29 Oct 2026 · measured differently
- Offering a track: not measured → relay offered nothing.
- New violation: One Track Alias must not be used for two tracks at once.
| Sweep | Reachable | Drafts | Delivery | Offers a track | Violations | Two publishers |
|---|---|---|---|---|---|---|
| 5 Nov 2026 | yes | 14, 16, 18, 22 | Object delivered end to end | relay offered nothing | 1 | no defects |
| 4 Nov 2026 | yes | 14, 16, 18, 22 | Object delivered end to end | relay offered nothing | 1 | no defects |
| 3 Nov 2026 | yes | 14, 16, 18, 22 | Object delivered end to end | relay offered nothing | 1 | no defects |
| 2 Nov 2026 | yes | 14, 16, 18, 22 | Object delivered end to end | relay offered nothing | 1 | no defects |
| 1 Nov 2026 | yes | 14, 16, 18, 22 | Object delivered end to end | relay offered nothing | 1 | no defects |
| 31 Oct 2026 | yes | 14, 16, 18, 22 | Object delivered end to end | relay offered nothing | 1 | no defects |
| 30 Oct 2026 | yes | 14, 16, 18, 22 | Object delivered end to end | relay offered nothing | 1 | no defects |
| 29 Oct 2026 | yes | 14, 16, 18, 22 | Object delivered end to end | relay offered nothing | 1 | no defects |
| 27 Oct 2026 | yes | 14, 16, 18, 22 | Object delivered end to end | — | — | — |
Notes
- — The endpoint is up and refused the offered protocols on at least one transport.
Is this your relay?
If something here is wrong, tell us — we keep what each result rests on, so a disputed one gets re-read rather than re-argued. We can also run this against endpoints that are not public.