Right, I just mean the calculation is completely different.  Tc = Bc/CIR is
only relevant for shaping.  Tc with policing is an entirely different
concept.

On Mon, Apr 23, 2012 at 12:31 PM, Kingsley Charles <
[email protected]> wrote:

> Tc is involved in both shaping and policing.
>
> With policing, Tc is the seconds for which tokens are put in the bucket.
>
> With regards
> Kings
>
>
> On Mon, Apr 23, 2012 at 7:26 PM, Joe Astorino 
> <[email protected]>wrote:
>
>> The forumulas for calculating the Bc and Be for policing are how you have
>> defined, them but I would be careful with the use of the term "Tc" when
>> dealing with policing.  Tc is generally a term that applies to traffic
>> shaping and not traffic policing.  Why?  What does Tc do for us?  With a
>> shaper, Tc is a static defined interval of time.  As you know, each Tc
>> interval we get to add Bc tokens to the bucket to use.  Traffic policing
>> does not work the same way, contrary to popular belief. With traffic
>> policing, the token bucket is refreshed based on a function of 2 things:
>> The CIR value and the amount of time passed since the last packet was
>> received.  It has nothing to do with Tc.
>>
>> My point is simply that Tc is not involved with the calculations of
>> traffic policing, as it is a concept that applies to traffic shaping.
>>
>> On Sun, Apr 22, 2012 at 12:32 PM, Kingsley Charles <
>> [email protected]> wrote:
>>
>>> Hi all
>>>
>>> The following is how we calculate Bc for QoS MQC policing and TCP
>>> rate-limiting. Now for ZPF policing, which formula should be used. I need
>>> Cisco doc for confirmation.
>>>
>>>
>>> Policing
>>> ========
>>>
>>> Tc = 0.25 secs
>>>
>>> BC = CIR/8 * 0.25 = CIR/32
>>>
>>> Be = Bc, if not specified
>>>
>>>
>>> TCP Rate-limiting
>>> =============
>>>
>>> Tc = 1.5 secs
>>>
>>> BC = CIR/8 * 1.5
>>>
>>> BE = 2 BC
>>>
>>>
>>> With regards
>>> Kings
>>>
>>> _______________________________________________
>>> For more information regarding industry leading CCIE Lab training,
>>> please visit www.ipexpert.com
>>>
>>> Are you a CCNP or CCIE and looking for a job? Check out
>>> www.PlatinumPlacement.com
>>>
>>
>>
>>
>> --
>> Regards,
>>
>> Joe Astorino
>> CCIE #24347
>> http://astorinonetworks.com
>>
>> "He not busy being born is busy dying" - Dylan
>>
>>
>


-- 
Regards,

Joe Astorino
CCIE #24347
http://astorinonetworks.com

"He not busy being born is busy dying" - Dylan
_______________________________________________
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