| Class | Description | 
|---|---|
| NodeSchedulerService | 
 A first pass of a simple  
interface SchedulerService that works with class MutableClocks for testing, demonstrations and simulations
that also encompasses the class Vault observer for processing transactions. | 
| ScheduledActivityObserver | 
 This observes the vault and schedules and unschedules activities appropriately based on state production and
consumption. 
 |