In EPL applications, everything in a monitor instance is private. There is no direct way for a monitor instance to invoke an action or access the state of another monitor instance. Instead, messages, in the form of events, are the mechanism for communication among monitor instances. All events are visible to all interested monitor instances.

Consequently, how you divide your application operations into monitors and what events the monitor instances use to communicate are crucial design decisions. Also, you might want to use the MemoryStore correlator plug-in to share state between monitors. See Using the MemoryStore.