Struggling to get my head around this concept: what data is marked as "exceeding" in a single rate 3 color policer...

OK so as far as I have read up on in a Two-rate Three-color policer, traffic markes as exceeding is anything above the CIR and below the PIR within a Tc timespan., anything that exceeds the PIR is considered violating, this makes sence to me.

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I'm not quite understaning what traffic will be marked as exceeding in a single-rate three colour policer, would that be all traffic that matches, let's say Tc window is 200msec, would traffic marked as exceeding be any data within Tc window that exceeds Bc, and is below Be ? if so whtat is the point of having a two-rate policer, couldnt you just keep increasing the Be to ahve the same result?

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Or would exceeding be a burst within that 200msec average that exceeds both Bc and Be data/bytes, I assumed that traffic would be marked as violating.

Take below example =

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police 64000 bc 1600 be 2400

Tc window 200msec : | ( 800 Bytes) -- ( 900 Bytes) |

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That last 100 Bytes in the 2nd burst exceeds the Bc, so would that be considered exceeding or violating ? does it depend on wether or not we have surpluss tokens in the Be bucket? I am assuming exceeding in this scenario would be any data that has use tokens from the Be .

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If anyone could explain this to me or point me to a good document, that would be appreciated.