TR 101 290 monitoring: requirements (broadcast/contribution health metrics)

[t0ms]

Goal

For MoQ to replace satellite/contribution links and hand off to IRDs, it needs the
stream-health telemetry operators expect from SRT / Zixi / RIST. ETSI TR 101 290 is the
industry yardstick for MPEG-TS integrity. This issue specifies what to monitor and
where to surface it, so we can agree scope before building a skeleton. Part of #1799.
No implementation here, requirements only.

Where monitoring runs (design question)

The relay core is media-agnostic by design, so TS-level monitoring belongs at the TS
edges, not in the relay:

• Ingest (e.g. moq-srt, moq-cli publish ts): validate the incoming contribution
  feed and expose its health.
• Egress (e.g. moq-srt m=request, moq-cli subscribe --format ts): validate the
  TS we hand downstream.
  Important nuance from the two-lane model (Proposal: broadcast contribution profile for MoQ (faithful TS / satellite replacement) #1799):
• Media-aware lane (today): PAT/PMT/PCR/CC are regenerated by our muxer, so at
  egress TR 101 290 mostly validates our own output (still valuable, catches muxer
  regressions like the DTS issue fix(moq-mux): author DTS for B-frame MPEG-TS export (decode timeline not emitted) #1836). SI tables beyond PAT/PMT don't exist in this
  lane, so those checks are N/A.
• Opaque whole-mux lane (future, Option B): the original PCR cadence, CC, and SI
  survive, so TR 101 290 validates the real contribution feed faithfully. This is where
  full P1/P2/P3 conformance is meaningful.
  Proposed: implement the checks once over a TS byte/packet stream, run them at both edges,
  and surface results through the existing stats plumbing (cf. feat(libmoq, moq-ffi): expose connection stats #1783 connection stats,
  feat(moq-net,moq-cli): per-track stats + moq-cli --stats usage display #1671 per-track stats; moq-net/moq-relay stats modules).

Checks to implement (configurable thresholds; ETSI defaults)

Priority 1 (loss of these = not decodable)

• TS_sync_loss (loss of sync after N consecutive bad sync bytes; default 5)
• Sync_byte_error (sync byte != 0x47)
• PAT_error / PAT_error_2 (PAT absent, repetition > 0.5 s, PID 0 wrong table_id, scrambled)
• Continuity_count_error (CC discontinuity / wrong increment / illegal duplicate)
• PMT_error / PMT_error_2 (PMT repetition > 0.5 s, scrambled)
• PID_error (a referenced PID not seen within a user-defined window)

Priority 2 (recommended continuous monitoring)

• Transport_error (TEI bit set)
• CRC_error (PAT/PMT/CAT/NIT/EIT/BAT/SDT CRC)
• PCR_repetition_error (PCR interval > 40 ms)
• PCR_discontinuity_indicator_error (> 100 ms jump w/o discontinuity_indicator)
• PCR_accuracy_error (PCR drift outside +/- 500 ns)
• PTS_error (PTS repetition interval > 700 ms)
• CAT_error (CAT required when scrambling present)

Priority 3 (application dependent; mostly opaque-lane only)

• NIT/SDT/EIT/TDT/RST_error, SI_repetition_error, unreferenced_PID

Surfacing

• Per-check counters + last-event timestamp, per PID where applicable.
• Aggregate per-stream "health" suitable for an operator dashboard (green/amber/red per
  priority, akin to an SRT/Zixi stats panel).
• Exposed through the existing stats API so relay/CLI consumers can read it; no new
  bespoke transport.

Out of scope (for now)

• Remediation (FEC, 2022-7) - separate egress work.
• Full DVB SI semantic validation beyond presence/repetition/CRC.
• A GUI; this is the metrics source, not a dashboard.

Open questions for discussion

1. Does monitoring live in a dedicated moq-ts/moq-monitor crate, or inside the
   ingest/egress crates that already touch TS?
2. Which subset is MVP, P1 + the PCR/CC/PTS parts of P2?
3. Configuration surface (thresholds, which PIDs, sampling) - CLI flags vs config file.
   A private reference implementation of these checks exists and can inform thresholds and
   edge cases; happy to share it as background (not as a code drop).
   (Written by Claude)

[coderabbitai]

🔗 Related PRs

#1773 - fix(moq-relay,moq-native): stop the cert-reload busy loop, then dedupe FileWatcher [merged]
#1808 - moq-gst: fix plugin license + broadcast-aligned timestamps [merged]
#1812 - fix(moq-mux): carry all distinct SPS/PPS/VPS through transmux, not just the last seen [merged]
#1815 - feat(moq-mux): generic verbatim MPEG-TS carriage (mpegts catalog section) [merged]

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