Goal

User believes the DSR is throttling specific connections, although measurement reports indicate Maximum Ingress MPS for the connections has not been exceeded.

Solution

The connection referred to seem to be very spiky. The connection is getting throttled even with it set for 160mbs.
A connection can have a low average mbs and still exceed the throttled level by spiking high for a relatively short period.

The real question is:
Is there a way to tell what the high level, mbs, is for a connection?
Answer: - Please refer "Ingress Msgs Per Second" column of the Main Menu: Diameter -> Maintenance -> Connections Screen for the current average traffic rate of the connection.  

Are there KPIs that can be used to determine what is the high, low and average mbs per connection?
If no KPI exist, how can the high level be determined?
Answer: - There are no KPI's for the Per connection Ingress Traffic rate.
The following measurements works on the Exponentially smoothed average algorithm.
So, there is a definite convergence time and there is a fair chance to miss the sudden spike in the traffic.
If traffic spike continues for a while, then average and peak would be close to the real values.

10500|RxConnAvgMPS|Arrayed|Average|5min|TransportConnection||ES|StatClerk1|B||Exponentially smoothed average rate in MPS on the connection.
10501|RxConnPeakMPS|Arrayed|Max|5min|TransportConnection||ES|StatClerk1|B||Peak rate of the exponentially smoothed average rate in MPS on the connection.

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