What is the difference between "Brokers UP" and "Services UP"?

In SCDS two Message Brokers, EMS1 and EMS2 are utilized within AWS to route messages from NEMS to users on SCDS. The "Brokers Up" or "Brokers "Down" will indicate the health status of those Brokers. "Services Up" or "Services Down" will indicate the health status of the SWIM producer services.