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police question(about token bucket concept) posted 01/17/2008
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Dear all,

I am not understand the concept of the token bucket, so please
someone verify below case and tell me does it correct. If it is correct, I
have 1 more question which is base on it.

police 8000 1000 conform-action
transmit exceed-action drop
cir = 8000 bps
bc = 1000 byte = 8000 bit
If the
1st packet is 500 bytes size. It takes 0.5s to transmit this packet and this
packet will be under conform action(transmit). There is 4000 bit left in the
token bucket. 
If the 2nd packet arrive in 0.1s later, the token bucket
"charge" 800 bit(CIR[8kbps] x 0.1s) and 4800 bit in token bucket when 2nd
pakcet arrive. If the 2nd packet is smaller than 600byte(4800bit), then packet
can be transmit because the token bucket capacity available. The the 2nd
packet is bigger than 600byte, it will fall into the exceed action, which is
drop.

If the above concept is correct, I have a question. If there is a
traffic pattern which the packets are transmitted with no idle gap. What will
happen in 1 second after? (cir =  8kbps, bc = 8k also)

Thanks & Regards,
Howard


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