The three machines
| Meeting | Webinar | Town hall | |
|---|---|---|---|
| Engine | Interactive conference | Interactive conference + registration front-end | Streaming pipeline (like view-only overflow, for everyone) |
| Audience | Known invitees | Registrants (approval, capacity, reminders) | Up to 10,000 (20,000 Premium); link or targeted |
| Attendee experience | Full participation | Participation as configured | Watch + moderated Q&A; seconds of delay |
| Presenter workflow | None | Structured roles | Green room, producer view, managed sources |
| Delivery aid | — | — | eCDN for on-network scale |
| Licensing (since Apr 2026) | Base | Base incl. advanced basics | Base; Premium = 20k, more production/customisation |
Decision rule that survives contact with reality: conversation → meeting; managed audience who might speak → webinar; produced broadcast where the audience watches → town hall. Attendee count is secondary — a 3,000-person "ask us anything" is a town hall with Q&A, not a giant meeting, and the 1,000-wall (previous concept) enforces that whether you planned it or not.
The parts people under-plan
- Registration is a data asset: capacity caps, manual approval, custom questions — and the attendee report joins registration to actual attendance. For external webinars, that's marketing's lead list; treat the export access accordingly.
- Town hall Q&A is the only backchannel — attendees have no mic, no chat; if you don't staff Q&A moderation, your event has no audience contact at all.
- The delay is structural (streaming pipeline): presenters answering live chat from a parallel meeting will be ~10-30s ahead of what attendees see — brief your hosts, every time.
- eCDN: above a few hundred concurrent on-network viewers, unicast from Microsoft saturates the WAN edge; eCDN (Microsoft's or partner) peers/caches inside your network. Verify BEFORE the CEO event, not during (see the eCDN concept).
What to watch (proofs)
- Policy gates:
Get-CsTeamsEventsPolicy | fl— who may create webinars/town halls, external registration allowed or not (in our nightly scan; TownhallEventAttendeeAccess already appears in your search results from the tenant). - An event's true engine: town halls appear in the TAC events tooling with streaming telemetry; meetings never do — if the "webinar" shows conference telemetry only, someone made a meeting with a registration page.
- Attendance truth: the event's attendance + registration reports (organizer view / Graph) — registrants vs attendees vs drop time series.
- Delay measurement: presenter clock vs attendee stream — measure once at rehearsal, publish the number to the production crew.