@startuml
skinparam shadowing false
title Heartbeat decision (every 5 min)

[*] --> Down
Down --> Up : probe answers\n/ heartbeat EnemyTerritory-1
Up --> Up : probe answers\n/ heartbeat EnemyTerritory-1
Up --> Down : no answer\n/ heartbeat ETFlatline-1 (once)
Down --> Down : no answer\n/ nothing sent
@enduml