How often do loggers upload measurement data into the system?

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What is "Aggregation"

An Aggregation is a group or mass of distinct or varied things. In the FMv2 system, an Aggregation that the same type of Events is merged together into one Event, for example, if all loggers inside a freezer measures too high temperature and all of them would activate an Event. In the FMv2 sytstem, these Events would merge into one Event. This is done to reduce the number of alerts that one can receive. 

What is "Propagation"?

When the system creates an Event, the Event can propagate up the Entity Tree. For example, there might be a person responsible for temperature monitoring in a single warehouse within one region. This person might subscribe to high severity temperature excursions at the Collection Level. When one measuring point creates a High-Temperature Event, the Event will travel up the Entity Tree, display the Event on the Collection Level, and send out an alert to users who have subscribed to them.

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