Set a check-in window
Choose 5–300 seconds. Each heartbeat restarts the same window.
Timer is idle.
30seconds
0 heartbeats sent in this session
Set the duration, then start the timer.
Design questions for a real workflow
- Who can send a heartbeat, and how is that identity verified?
- What happens if the device, clock or communication path fails?
- Who reviews an expiry event before any irreversible action?