Hello!
I'd like to point out one GREAT of your technical writers' mistake (or discrepancy - your may choose on your own) when they explan "Single-rate, Three-color policer". :-)
BE is ADDITIONAL TO BC NUMBER OF BYTES which is got during period of Sender's "silence" giving RIGHT to send EXTRA BYTES according to contract.
1) 128000 bps, 1 second: BC=16KBytes, OK?
2) 128000 bps, 1,5 seconds of no-transmittion: BC=16KBytes, BE=8 KBytes - right? This can be found in your documentation: "Understanding Single-Rate and Dual-Rate Traffic Policing", just look around: "By allowing customer to accumulate up to Be extra bytes during longer than normal wait intervals".
At the same time when you explain Single-rate, Three-color policing, you exemplify: first of all BC bucket is re-filled and then spilled out tockens are put into BE bucket, right? Then, when you analyze if a packet conforms to contract or exceeds one you compare:
If (PacketSize<BC) then CONFORM else
if(Packet>BC and PacketSize<=BE) then EXCEED else....
Let's will not follow the text and stop right here. And let's return to my (indeed, YOURS) Item 2). Please, explain me how could it be: BC=16K, BE=8K (AT THE SAME TIME)=8K and how can the packet be great than 16K and LESS OR EQUAL to 8K simultaneously ???
And all of us repeat and repeat it again as something like "mantra"... But I think it would be more correct if I say:
If (PacketSize<BC) then CONFORM else
if(Packet<=BC + BE) then EXCEED else....
Then BC - is empteid completely and in the case with BE - by the reminder of (PacketSize - BC).
You may tell me: Dear, look at the size of BC - where have you seen a packet (among Ethernet networks) of size 16000 BYTES long whereas MTU=1500?
But I saw an example:
police cir 64000 bc 1000 be 500 conform-action transmit exceed-action set-dscp-transmit 0 violate-action drop
BC and BE are, indeed, necessary for Tc calculation. So, here is no conflict (in my opinion).And logic of comparisions is not erroneous now.
Or, could your, please, give me (detailed) example which would explain EXACT work of such type policer.
Kind regards,
Ellad
