The EtsysSrvcLvlNetMeasureTable is mandatory.
The etsysSrvcLvlNetMeasureMetrics is set to a list of metrics
to be computed from the same raw packet exchange. Each step of
measurement delivers a singleton per chosen metric. Results are
timestamped and saved in the etsysSrvcLvlHistoryTable.
The etsysSrvcLvlNetMeasureTable typical usage consists in
providing network measure indices in order to allow aggregated
measures to perform aggregation on the results of network
measures.