That's my understanding of how they work.
This config was recently changed with the latest McAfe Agent extensions.
At the beginning it was 60 minutes for the Server Communication Interval and 5 minutes for the Enforcement Interval. This way a computer was reporting props and downloading new tasks/policies every hour and enforcing policies every 5 minutes so if any auser changed a setting on the local computer (disabling on-access for example) it would be overwriteen by ePO policy every 5 minutes (becuase I want to aplpy my ePO policy at any moment).
As per me I still have a 5 minutes for the Enforcement Interval
Correct - policy enforcement interval is local to the client. Agent-server communication interval is when the client talks to ePO to get the 'latest' policies and tasks.
For example, if users can modify product settings you might want a more frequent policy enforcement interval to counterbalance that. It's down to you and your installation to choose
Policy enforcement interval : This time Agent will communicate to ePO for any new policy.
Agent to server communication : This time Agent will send client and Threat events to ePO server.
Hope this will clear your doubts.