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Understanding QoS policing in the LAN.

I was reading about Lan QoS and has a question about policing in LAN environment.

I agree that in the WAN policing,using token buckets makes sense while restricting the bandwidth. For example an enterprise has a T1 connection (physical access rate of 1.5mbps)and contracted bandwith is 128 kbps. In this case each T1 timeslot is 125ms and IOS adjusts the duration it sends the data(which is less than 125ms). So each Timeslot would have a active period and a lull period. Duting each time it would send the commited Bc bytes.

But in LAN environment,where a switch has only fastethernet (typically),eg 2590, what is the significance of the policing command

police <rate-bps>< Burst-bytes>[exceed-action{drop | dscp dscp-value]

Since its fast ethernet connection where is the question of Tc ?. If Tc is not relavant what is the significance of Bc ?.

Any pointer on this is highly apprciated.

Thanks in Advance,



Re: Understanding QoS policing in the LAN.


That's a good question - with lots of answers....but I will let the QoS SRND enlighten!


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