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Queuing with policing, yes that can be confusing since their goals are different. Queuing buffers packets when their arrival rate exceeds transmission rate. While queued, we can often define policies that determine transmission sequence different from arrival sequence. (Often the "secret ingredient" for QoS.)
Policing measures transmission rate based on optional selection criteria. Depending on transmission rate measurement, it may mark packets differently or discard packets.
Where the two overlap, queuing has a finite capacity and it too will discard packets. Policing can often be configured to allow temporary burst transmissions, so at least with regard to dropping packets, it can behave like a queue with some defined capacity.
Where they differ, policing does not resequence packets nor add additional queuing latency.
