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Re: [RPRWG] ConservativeRate SM questions



Necdet,

Thank you for quick response and help. Appreciated!

Regarding the 1st item below, the condition probably should just be
localFairRate >= unreservedRate[myRi].
That is, the left side need NOT be divided by localWeight.
Generally, a reasonable localFairRate should be <= unrevervedRate.
When localFairRate ramps up and reaches or exceeds unreservedRate,
localCongestion condition can be cleared.

Regards,
Guoliang


Necdet Uzun wrote:

> Guoliang,
>
> Please see below.
>
> Thanks.
>
> Necdet
>
> Guoliang Wu wrote:
>
>> Hello RPR experts:
>>
>> I have some questions regarding the conservative rate adjust State 
>> Machine
>> from the released RPR standard (802.17-2004.pdf, Table 10.9, pages 
>> 258 - 259).
>>
>> 1. Row 5: the condition is
>>     localFairRate/localWeight >= unreservedRate[myRi] - rampUpCoef.
>
>
> This is a typo. - rampUpCoef should not be there. I.e., it should be 
> just:
> localFairRate/localWeight >= unreservedRate[myRi]
>
>>   It seems having some typo in the right side, because unreservedRate 
>> is in bytes and
>>    rampUpCoef is a pure number.
>> 2.  Row 5 and Row 16: the allowedRate is calculated twice in the
>>      two states, first in Row 5 as
>>       allowedRate += (maxAllowedRate - allowedRate) / rampUpCoef;
>>   then after transiting from CGST state to FINAL state,
>>         allowedRate = Min(unreservedRate[myRi], localFairRate);
>
> You are right, the calculation in row 5:
>
> allowedRate += (maxAllowedRate - allowedRate) / rampUpCoef;
>
> is not needed (and overwritten later) as allowedRate has to be set to 
> normalized localFairRate in conservative mode of operation.
>
>>    The later calculation invalids the early one. One of the 
>> calculations should be
>>    removed or changed.
>>    Hope someone can clarify. Your help will be greatly appreciated!
>>
>> Regards,
>> Guoliang Wu
>> Fujitsu Network Communications, Inc.
>> Richardson, TX 75082
>>    
>
>